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Geologic units containing Shale

Shale
A laminated, indurated rock having more than 67% clay-sized minerals.
Subtopics:
Black shale
Oil shale

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Alabama

Athens Shale and Lenoir Limestone undifferentiated (Ordovician)
Athens Shale and Lenoir Limestone undifferentiated - Athens Shale -- black graptolitic shale, locally contains interbedded dark-gray limestone. Lenoir Limestone -- dark-gray medium to thick-bedded argillaceous limestone; locally contains an interval of fenestral mudstone at the base (Mosheim Limestone Member).
Attalla Chert Conglomerate Member of the Chickamauga Limestone (Ordovician)
Attalla Chert Conglomerate Member of the Chickamauga Limestone - conglomerate of pebbles, cobbles, and boulders of chert and rare dolomite and quartzite in a sand-sized chert and quartz matrix; thin beds of gray-green or dusky-red shale common at base.
Attalla Chert Conglomerate Member of the Chickamauga Limestone (Ordovician)
Attalla Chert Conglomerate Member of the Chickamauga Limestone - conglomerate of pebbles, cobbles, and boulders of chert and rare dolomite and quartzite in a sand-sized chert and quartz matrix; thin beds of gray-green or dusky-red shale common at base.
Bangor and Monteagle Limestones undivided in part (Mississippian)
Bangor and Monteagle Limestones undivided in part - Bangor Limestone -- medium-gray bioclastic and oolitic limestone, containing interbeds of dusky-red and olive-green mudstone in upper part. Monteagle Limestone -- light-gray oolitic limestone containing interbedded argillaceous, bioclastic, or dolomitic limestone, dolomite, and medium-gray shale.
Chattanooga Shale (Devonian)
Chattanooga Shale - Brownish-black organic shale containing light to dark-gray sandstone and rare limestone interbeds near the base.
Chattanooga Shale (Devonian)
Chattanooga Shale - Brownish-black organic shale containing light to dark-gray sandstone and rare limestone interbeds near the base.
Chattanooga Shale (Devonian)
Chattanooga Shale - Brownish-black organic shale containing light to dark-gray sandstone and rare limestone interbeds near the base.
Chattanooga Shale and Frog Mountain Sandstone undifferentiated (Devonian)
Chattanooga Shale and Frog Mountain Sandstone undifferentiated (In areas mapped as Dcfm one or both units may be locally absent) - Chattanooga Shale -- Brownish-black organic shale containing light to dark-gray sandstone and rare limestone interbeds near the base. Frog Mountain Sandstone -- light to dark-gray sandstone with thin dark-gray shale interbeds, light-gray to black dolomudstone, glauconitic limestone, and fossiliferous chert locally in lower part.
Chickamauga Limestone (Ordovician)
Chickamauga Limestone - Medium to dark-gray thick to thin-bedded partly argillaceous, locally fossiliferous limestone. Restricted to the western part of the Valley and Ridge province and Murphrees Valley and Wills Valley anticlines. Locally includes a thin interval of Attalla Chert Conglomerate Member at base. Attalla Chert Conglomerate - conglomerate of pebbles, cobbles, and boulders of chert and rare dolomite and quartzite in a sand-sized matrix; thin beds of gray-green or dusky-red shale common at base.
Chickamauga Limestone (Ordovician)
Chickamauga Limestone - Medium to dark-gray thick to thin-bedded partly argillaceous, locally fossiliferous limestone. Restricted to the western part of the Valley and Ridge province and Murphrees Valley and Wills Valley anticlines. Locally includes a thin interval of Attalla Chert Conglomerate Member at base. Attalla Chert Conglomerate - conglomerate of pebbles, cobbles, and boulders of chert and rare dolomite and quartzite in a sand-sized matrix; thin beds of gray-green or dusky-red shale common at base.
Conasauga Formation (Cambrian)
Conasauga Formation - light to dark-gray finely to coarsely crystalline, medium to thick-bedded dolomite containing minor greenish-gray shale and light-bluish-gray chert. In the Columbiana area of Shelby County, the Conasauga is dominated by thin to medium-bedded, dark-gray dolomitic limestone and minor dark-gray shale. In Bibb County and southwestern Shelby County, the Conasauga consists of medium-bluish-gray fine-grained, thin-bedded argillaceous limestone and interbedded dark-gray shale. In the eastern Valley and Ridge the lower part includes dark-green to pale-olive fossiliferous shale with a few dark-gray limestone interbeds.
Conasauga Formation (Cambrian)
Conasauga Formation - medium-bluish-gray fine-grained, thin-bedded argillaceous limestone and interbedded dark-gray shale in varying proportions.
Conasauga Formation (Cambrian)
Conasauga Formation - Medium-bluish-gray fine-grained, thin-bedded argillaceous limestone and interbedded dark-gray shale in varying proportions.
Conasauga Formation, lower unnamed shale facies (Cambrian)
Conasauga Formation, lower unnamed shale facies - lower unnamed shale facies in eastern Valley and Ridge consists of dark-green to pale-olive fossiliferous shale with a few dark-gray limestone interbeds.
Floyd Shale (Mississippian)
Floyd Shale - Dark-gray shale, sideritic in part; thin beds of sandstone, limestone and chert are locally present; beds of partly bioclastic, partly argillaceous limestone are abundant in parts of Calhoun and Cherokee Counties.
Fort Payne Chert (Mississippian)
Fort Payne Chert - Very light to light-olive-gray, thin to thick-bedded fine to coarse-grained bioclastic (abundant pelmatozoans) limestone containing abundant nodules, lenses and beds of light to dark-grey chert. Upper part of formation locally consists of light-bluish-gray laminated siltstone containing vugs lined or filled with quartz and scattered throughout the formation are interbeds of medium to greenish-gray shale, shaly limestone and siltstone. Commonly present below the Fort Payne is a light-olive-gray claystone or shale (Maury Formation) which is mapped with the Fort Payne. The apparent thickness of the Fort Payne in this province varies due to differnetial dissolution of carbonate in the formation.
Fort Payne Chert (Mississippian)
Fort Payne Chert - Very light to light-olive-gray, thin to thick-bedded fine to coarse-grained bioclastic (abundant pelmatozoans) limestone containing abundant nodules, lenses and beds of light to dark-grey chert. Upper part of formation locally consists of light-bluish-gray laminated siltstone containing vugs lined or filled with quartz and scattered throughout the formation are interbeds of medium to greenish-gray shale, shaly limestone and siltstone. Commonly present below the Fort Payne is a light-olive-gray claystone or shale (Maury Formation) which is mapped with the Fort Payne.
Frog Mountain Sandstone (Devonian)
Frog Mountain Sandstone -- light to dark-gray sandstone with thin dark-gray shale interbeds, light-gray to black dolomudstone, glauconitic limestone, and fossiliferous chert locally in lower part.
Greensport Formation (Ordovician)
Greensport Formation - variegated dusky-red and dark-yellowish-orange shale, calcareous mudstone, limestone, siltstone, and minor sandstone.
Hartselle Sandstone (Mississippian)
Hartselle Sandstone - Light-colored thick-bedded to massive quartzose sandstone, containing interbeds of dark-gray shale.
Hartselle Sandstone (Mississippian)
Hartselle Sandstone - Light-colored thick-bedded to massive quartzose sandstone, containing interbeds of dark-gray shale.
Hartselle Sandstone (Mississippian)
Hartselle Sandstone - Light-colored thick-bedded to massive quartzose sandstone, containing interbeds of dark-gray shale.
Inman Formation (Ordovician)
Inman Formation - interbedded greenish-gray or moderate to dusky-red shale and light-gray peloidal limestone. Mapped in Sequatchie Valley.
Monteagle Limestone (Mississippian)
Monteagle Limestone - Light-gray oolitic limestone containing interbedded argillaceous, bioclastic, or dolomitic limestone, dolomite, and medium-gray shale.
Monteagle Limestone (Mississippian)
Monteagle Limestone - Light-gray oolitic limestone containing interbedded argillaceous, bioclastic, or dolomitic limestone, dolomite, and medium-gray shale.
Monteagle Limestone (Mississippian)
Monteagle Limestone - Light-gray oolitic limestone containing interbedded argillaceous, bioclastic, or dolomitic limestone, dolomite, and medium-gray shale.
Nashville and Stones River Groups undifferentiated (Ordovician)
Nashville and Stones River Groups undifferentiated - medium to dark-gray fossiliferous limestone, argillaceous in part; yellowish-gray laminated silty limestone in upper part. Contains one or more thin beds of bentonite and bentonitic shale.
Ordovician System undivided in part (Includes Sequatchie Formation, Elkmont Formation, Leipers Limestone, Inman Formation, Nashville Group, and Stones River Group) (Ordovician)
Ordovician System undivided in part (Includes Sequatchie Formation, Elkmont Formation, Leipers Limestone, Inman Formation, Nashville Group, and Stones River Group) - Sequatchie Formation -- grayish-red and yellowish-gray calcareous shale containing interbedded fossiliferous limestone. Elkmont Formation -- medium to dark-gray phosphatic limestone with interbeds of light to medium-gray and black shale. Leipers Limestone -- medium to dark-gray thin to medium-bedded fossiliferous limestone containing interbeds of argillaceous limestone. Inman Formation -- interbedded greenish-gray or moderate to dusky-red shale and light-gray peloidal limestone. Nashville Group undifferentiated -- medium to dark-gray argillaceous and fossiliferous limestone overlain by yellowish-gray laminated silty limestone. Stones River Group -- medium to dark-gray thick to thin-bedded limestone, argillaceous in part, locally very fossiliferous.
Paleozoic shale undifferentiated (Mississippian)
Paleozoic shale undifferentiated - Dark-gray shale and mudstone, locally containing thin interbeds and lenses of dark-greenish-gray sandstone includes probable Floyd Shale in area east of Gadsden, Etowah County.
Paleozoic shale undifferentiated (Mississippian)
Paleozoic shale undifferentiated - Dark-gray shale and mudstone, locally containing thin interbeds and lenses of dark-greenish-gray sandstone includes Athens Shale and probable Floyd Shale in the structural windows near Anniston, Calhoun County.
Parkwood and Pennington Formations (Pennsylvanian-Mississippian)
Parkwood and Pennington Formations undifferentiated - Interbedded medium to dark-gray shale and light to medium-gray sandstone, locally contains lithic conglomerate, dusky-red and grayish-green mudstone, argillaceous limestone, and clayey coal.
Parkwood and Pennington Formations undifferentiated (Pennsylvanian-Mississippian)
Parkwood and Pennington Formations undifferentiated - Interbedded medium to dark-gray shale and light to medium-gray sandstone, locally contains lithic conglomerate, dusky-red and grayish-green mudstone, argillaceous limestone, and clayey coal.
Parkwood Formation (Pennsylvanian-Mississippian)
Parkwood Formation - Interbedded medium to dark-gray shale and light to medium-gray sandstone; locally contains dusky-red and grayish-green mudstone, argillaceous limestone, and clayey coal.
Parkwood Formation (Pennsylvanian-Mississippian)
Parkwood Formation - Interbedded medium to dark-gray shale and light to medium-gray sandstone; locally contains dusky-red and grayish-green mudstone, argillaceous limestone, and clayey coal.
Parkwood Formation and Floyd Shale undifferentiated (Pennsylvanian-Mississippian)
Parkwood Formation and Floyd Shale undifferentiated - Parkwood Formation -- Interbedded medium to dark-gray shale and light to medium-gray sandstone; locally contains dusky-red and grayish-green mudstone, argillaceous limestone, and clayey coal. Floyd Shale -- Dark-gray shale, sideritic in part; thin beds of sandstone, limestone and chert are locally present; beds of partly bioclastic, partly argillaceous limestone are abundant in parts of Calhoun and Cherokee Counties.
Pennington Formation (Mississippian)
Pennington Formation - Medium-gray shale, containing interbedded limestone, dolomite, argillaceous sandstone, dusky-red and grayish-olive mudstone, and minor shaly coal. Mainly restricted to eastern part of Interior Low Plateaus province and where less than 100 feet thick the formation is included in the Bangor Limestone.
Pennington Formation (Mississippian)
Pennington Formation - Medium-gray shale, containing interbedded limestone, dolomite, argillaceous sandstone, dusky-red and grayish-olive mudstone, and minor shaly coal. Mainly restricted to northeastern AL and part of the Sequatchie anticline. Where less than 100 feet thick the formation is included in the Bangor Limestone.
Pottsville Formation (Pennsylvanian)
Pottsville Formation - Light-gray thin to thick-bedded quartzose sandstone and conglomerate containing interbedded dark-gray shale, siltstone, and coal. Mapped on Lookout Mountain, Blount and Chandler Mountains, and Sand Mountain northeats of Blount County, and on the mountains of Jackson, Marshall and Madison Counties north and west of the TN river.
Pottsville Formation (lower part) (Pennsylvanian)
Pottsville Formation (lower part) - Light-gray thick-bedded to massive pebbly quartzose sandstone, containing varying amounts of interbedded dark-gray shale, siltstone, and thin discontinuos coal. In both the Cahaba and Coosa synclinoria the members in descending order include: the Pine Sandstone Member and the Shades Sandstone Member. Top of unit is mapped at top of Pine Sandstone Member.
Pottsville Formation (lower part) (Pennsylvanian)
Pottsville Formation (lower part) - Light-gray thick-bedded to massive pebbly quartzose sandstone, containing varying amounts of interbedded dark-gray shale, siltstone, and thin discontinuos coal. The Boyles Sandstone Member is a formally named unit in the lower part of the formation. Top of unit is mapped at the Black Creek coal.
Pottsville Formation (upper part) (Pennsylvanian)
Pottsville Formation (upper part) - Interbedded dark-gray shale, siltstone, medium-gray sandstone, and coal in cyclic sequences. In descending order the members include: Razburg Sandstone Member, Camp Branch Sandstone Member, Lick Creek Sandstone Member, and the Bremen Sandstone Member.
Pottsville Formation (upper part) (Pennsylvanian)
Pottsville Formation (upper part) - Interbedded dark-gray shale, siltstone, medium-gray sandstone, and coal in cyclic sequences. The members present in the Cahaba synclinorium in descending order include: the Straven Conglomerate Member, Rocky Ridge Sandstone Member, and Chestnut Sandstone Member. The members present in the Coosa synclinorium in descending order include: Straight Ridge Sandstone Member and Wolf Ridge Sandstone Member.
Pride Mountain Formation (Mississippian)
Pride Mountain Formation - Medium to dark-gray shale, containing one to three units of a variable combination of sandstone and limestone in the lower part; locally contains rare interbeds of dusky-red and greenish-gray mudstone.
Pride Mountain Formation (Mississippian)
Pride Mountain Formation - Medium to dark-gray shale, containing one to three units of a variable combination of sandstone and limestone in the lower part; locally contains rare interbeds of dusky-red and greenish-gray mudstone.
Pride Mountain Formation (Mississippian)
Pride Mountain Formation - Medium to dark-gray shale, containing one to three units of a variable combination of sandstone and limestone in the lower part; locally contains rare interbeds of dusky-red and greenish-gray mudstone.
Pride Mountain Formation and Monteagle Limestone undifferentiated (Mississippian)
Pride Mountain Formation and Monteagle Limestone undifferentiated - Light-gray oolitic limestone, argillaceous and in part bioclastic with interbeds of medium to dark-gray shale.
Red Mountain Formation (Silurian)
Red Mountain Formation - dark-reddish-brown to olive-gray partly fossiliferous, mostly fine-grained sandstone interbedded with siltstone and shale; minor amounts of bioclastic limestone and conglomerate sandstone; includes hematitic beds and beds of ferruginous sandstone, outcrops in northeastern AL are finer grained and include more limestone.
Red Mountain Formation (Silurian)
Red Mountain Formation - Interbedded yellowish-gray to moderate-red sandstone, siltstone and shale; greenish-gray to moderate-red fossiliferous partly silty and sandy limestone; few thin hematitic beds.
Red Mountain Formation (Silurian)
Red Mountain Formation - Interbedded yellowish-gray to moderate-red sandstone, siltstone and shale; greenish-gray to moderate-red fossiliferous partly silty and sandy limestone; few thin hematitic beds.
Rome Formation (Cambrian)
Rome Formation - variegated thinly interbedded mudstone, shale, siltstone, and sandstone; limestone and dolomite occur locally. Quartzose sandstone commonly present near top of formation.
Sequatchie Formation (Ordovician)
Sequatchie Formation - Grayish-red, grayish-green, and yellowish-gray thin-bedded calcareous shale and calcareous mudstone containing interbedded fossiliferous limestone, and medium-gray to moderate-red partly sandy and glauconitic, medium to coarse-grained bioclastic limestone. In Jackson County, includes the Leipers Limestone and Inman Formation.
Sequatchie Formation (Ordovician)
Sequatchie Formation - dusky-red to light-olive-gray siltstone, sandstone, shale, and dolomite, regular but uneven bedding.
Sequatchie Formation (Ordovician)
Sequatchie Formation - light-olive-gray and dusky-red calcareous shale interbedded with light to dark-gray fine to coarse-grained partly bioclastic, argillaceous, locally glauconitic limestone.
Sequatchie Formation (Ordovician)
Sequatchie Formation - Grayish-red, grayish-green, and yellowish-gray thin-bedded calcareous shale and calcareous mudstone containing interbedded fossiliferous limestone, and medium-gray to moderate-red partly sandy and glauconitic, medium to coarse-grained bioclastic limestone.
Sequatchie Formation, Colvin Mountain Sandstone, Greensport Formation undifferentiated (Ordovician)
Sequatchie Formation, Colvin Mountain Sandstone, Greensport Formation undifferentiated - variegated dusky-red and pale-yellowish-orange shale, calcareous mudstone, dolomite, siltstone, and minor sandstone. Mapped in areas of facies transition with the Chickamauga Limestone (Canoe Creek, Dunaway, and Hensley Mountains).
Sequatchie Formation, Colvin Mountain Sandstone, Greensport Formation undifferentiated (Ordovician)
Sequatchie Formation, Colvin Mountain Sandstone, Greensport Formation undifferentiated - variegated dusky-red and pale-yellowish-orange shale, calcareous mudstone, dolomite, siltstone, and minor sandstone. Mapped in areas of facies transition with the Chickamauga Limestone (Scraper Mountain) and in the structurally complex area at the east end of Dry Creek Mountain.
Silurian System undivided (Includes Wayne Group and Brassfield Limestone) (Silurian)
Silurian System undivided (Includes Wayne Group and Brassfield Limestone) - Wayne Group - medium-gray, greenish-gray, and moderate-red argillaceous limestone; moderate-red and greenish-gray shale; and grayish-green fossiliferous limestone with scattered pink calcite crystals. Brassfield Limestone - greenish-gray to light-brownish-gray argillaceous, dolomitic, cherty, sandy, glauconitic limestone.
Stones River Groups undifferentiated in part (Ordovician)
Stones River Groups undifferentiated in part - medium to dark-gray thick to thin-bedded limestone, argillaceous in part, locally very fossiliferous. Contains a zone of bentonite and bentonitic shale near the top. Mapped seperately from the Nashville Group only in Jackson County.
Tuscumbia Limestone and Fort Payne Chert undifferentiated (Mississippian)
Tuscumbia Limestone and Fort Payne Chert undifferentiated - Tuscumbia Limestone -- light to dark-gray fossiliferous and oolitic partly argillaceous and cherty limestone. Apparently present only along part of the northwest limb of the Coosa synclinorium. Fort Payne Chert -- dark-gray to light-gray limestone with abundant irregular light-gray chert nodules and beds. Commonly present below the Fort Payne is greenish-gray to grayish-red phosphatic shale (Maury Formation) which is mapped with the Tuscumbia Limestone and Fort Payne Chert undifferentiated.
Tuscumbia Limestone and Fort Payne Chert undifferentiated (Mississippian)
Tuscumbia Limestone and Fort Payne Chert undifferentiated - Tuscumbia Limestone -- light to dark-gray fossiliferous and oolitic partly argillaceous and cherty limestone, absent locally and too thin to map seperately. Fort Payne Chert -- dark-gray to light-gray limestone with abundant irregular light-gray chert nodules and beds. Commonly present below the Fort Payne is greenish-gray to grayish-red phosphatic shale (Maury Formation) which is mapped with the Tuscumbia Limestone and Fort Payne Chert undifferentiated.
Tuscumbia Limestone and Fort Payne Chert undivided (Mississippian)
Tuscumbia Limestone and Fort Payne Chert undivided - Tuscumbia Limestone -- light-gray partly oolitic limestone; very coarse bioclastic crinoidal limestone common; light-gray chert nodules and concretions locally abundant. Fort Payne Chert -- very light to light-olive-gray, thin to thick-bedded fine to coarse-grained bioclastic (abundant pelmatozoans) limestone containing abundant nodules, lenses and beds of light to dark-grey chert. Upper part of formation locally consists of light-bluish-gray laminated siltstone containing vugs lined or filled with quartz and scattered throughout the formation are interbeds of medium to greenish-gray shale, shaly limestone and siltstone. Lenses of dark-gray siliceous shale occur locally at the base of the Fort Payne in Wills Valley. Commonly present below the Fort Payne is a ligh-olive-gray claystone or shale (Maury Formation) which is mapped with the Fort Payne. The Tuscumbia and Fort Payne are undifferentiated in Murphrees and Wills Valleys.

Arkansas

Arkansas Novaculite (Phanerozoic | Paleozoic | Devonian-Late Carboniferous Mississippian-Early)
Arkansas Novaculite - Includes upper division (Mississippian), middle division (Mississippian and Devonian), and lower division (Devonian)
Atoka Formation - Lower part (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atokan])
Atoka Formation - Lower part
Atoka Formation - Middle part (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atokan])
Atoka Formation - Middle part
Atoka Formation, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atokan] )
Atoka Formation, undivided
Atoka Formation - Upper part (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atokan])
Atoka Formation - Upper part
Blakely Sandstone (Middle and Lower Ordovician) (Phanerozoic | Paleozoic | Ordovician-Early Ordovician-Middle)
Blakely Sandstone (Middle and Lower Ordovician)
Bloyd Shale, and Prairie Grove Member of the Hale Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Morrowan])
Bloyd Shale, and Prairie Grove Member of the Hale Formation
Boggy Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Des Moinesian])
Boggy Formation
Boone Formation (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early [Meramecian Osagean])
Boone Formation
Cason Shale and Fernvale Limestone (Upper Ordovician) and Kimmswick Limestone, Plattin Limestone, and Joachim Dolomite (Middle Ordovician) (Phanerozoic | Paleozoic | Ordovician-Middle Ordovician-Late)
Cason Shale and Fernvale Limestone (Upper Ordovician) and Kimmswick Limestone, Plattin Limestone, and Joachim Dolomite (Middle Ordovician)
Chattanooga Shale (Lower Mississippian and Upper Devonian), Clifty Limestone (Middle Devonian), and Penters Chert (Lower Devonian) (Phanerozoic | Paleozoic | Devonian-Early Devonian-Middle(?) Devonian-Late(?) Carboniferous Mississippian-Early)
Chattanooga Shale (Lower Mississippian and Upper Devonian), Clifty Limestone (Middle Devonian), and Penters Chert (Lower Devonian)
Collier Shale (Phanerozoic | Paleozoic | Ordovician-Early)
Collier Shale
Cotter and Jefferson City Dolomites (Phanerozoic | Paleozoic | Ordovician-Early)
Cotter and Jefferson City Dolomites
Crystal Mountain Sandstone (Phanerozoic | Paleozoic | Ordovician-Early)
Crystal Mountain Sandstone
Harthshorne Sandstone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Des Moinesian])
Harthshorne Sandstone
Jackfork Sandstone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early [Morrowan])
Jackfork Sandstone
Johns Valley Shale (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early [Morrowan])
Johns Valley Shale
Mazarn Shale (Phanerozoic | Paleozoic | Ordovician-Early)
Mazarn Shale
McAlester Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Des Moinesian])
McAlester Formation
Missouri Mountain Shale and Baylock Sandstone (Phanerozoic | Paleozoic | Silurian)
Missouri Mountain Shale and Baylock Sandstone - The Baylock Sandstone is present only in the Cross, Cossatot, and Trap Mountains. Missouri Mountain Shale is mapped with Polk Creek Shale and Bigfork Chert in the area between Paron, Saline County, and Little Rock
Moorefield Formation (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late [Meramecian])
Moorefield Formation
Pitkin Limestone, Fayetteville Shale (including the Wedington Sandstone member), and Batesville Sandstone (including the Hindsville Limestone Member) (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late [Chesterian])
Pitkin Limestone, Fayetteville Shale (including the Wedington Sandstone member), and Batesville Sandstone (including the Hindsville Limestone Member)
Pole Creek Shale (Upper Ordovician) and Bigfork Chert (Upper and Middle Ordovician) (Phanerozoic | Paleozoic | Ordovician-Middle Ordovician-Late)
Polk Creek Shale (Upper Ordovician) and Bigfork Chert (Upper and Middle Ordovician)
Powell Dolomite (Phanerozoic | Paleozoic | Ordovician-Early)
Powell Dolomite
Ruddell Shale (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late [Chesterian])
Ruddell Shale
Savanna Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Des Moinesian])
Savanna Formation
Stanley Shale (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early)
Stanley Shale - Includes Chickasaw Creek Chert equivalent of Harlton (1938) near top and Hatton Tuff Lentil and Hot Springs Sandstone Member near base
Womble Shale (Middle Ordovician) (Phanerozoic | Paleozoic | Ordovician-Middle)
Womble Shale (Middle Ordovician)

Arizona

Cretaceous sedimentary rocks (Cretaceous)
Tan sandstone (Dakota Sandstone) overlain by gray shale (Mancos Shale); deposited in beach, river delta, and shallow sea settings. The Mancos Shale is overlain by the Mesaverde Group (map unit Kmv). This unit includes related sandstone and shale exposed near Show Low, Morenci (Pinkard Formation), and around Deer Creek south of Globe. (about 88-97 Ma)
Cretaceous to Late Jurassic sedimentary rocks with minor volcanic rocks (Late Jurassic to Cretaceous)
Sandstone and conglomerate, rarely forms prominent outcrops; massive conglomerate is typical near base of unit and locally in upper part. These deposits are nonmarine except in southeastern Arizona, where prominent gray marine limestone (Mural Limestone) forms the middle of the Bisbee Group. Sandstones are typically medium-bedded, drab brown, lithic-feldspathic arenites. Includes Bisbee Group (largely Early Cretaceous) and related rocks, Temporal, Bathtub, and Sand Wells formations, rocks of Gu Achi, McCoy Mountains Formation, and Upper Cretaceous Fort Crittenden Formation and equivalent rocks. (80-160 Ma)
Early Proterozoic metasedimentary rocks (Early Proterozoic)
Metasedimentary rocks, mostly derived from sandstone and shale, with minor conglomerate and carbonate rock. Includes quartz-rich, mostly nonvolcanic Pinal Schist in southeastern Arizona and variably volcanic-lithic sedimentary rocks in the Yavapai and Tonto Basin supergroups in central Arizona. (1600-1800 Ma)
Early Proterozoic quartzite (Early Proterozoic)
Brown to maroon, resistant quartzite and minor conglomerate of the Mazatzal Group, exposed primarily in the Payson area. (1650? -1700 Ma)
Middle Proterozoic sedimentary rocks (Middle Proterozoic)
Red-brown shale and sandstone, buff to orange quartzite, limestone, basalt, black shale, and sparse conglomerate. This unit includes the Grand Canyon Supergroup, Apache Group, and Troy Quartzite. These rocks were deposited in shallow marine, coastal nonmarine, and fluvial settings. (700-1300)
Mississippian, Devonian, and Cambrian sedimentary rocks (Cambrian, Devonian, and Mississippian)
Brown to dark gray sandstone grades upward into green and gray shale, overlain by light to medium gray or tan limestone and dolostone. This unit includes the Tapeats Sandstone, Bright Angel Shale, Muav Limestone, Temple Butte Formation and Redwall Limestone in northern Arizona, and the Bolsa Quartzite, Abrigo Formation, Martin Formation, and Escabrosa Limestone in southern Arizona. These rocks record intermittent sea-level rise and inundation in early Paleozoic time. (330-540 Ma)
Permian to Pennsylvanian sedimentary rocks (Pennsylvanian to Permian)
Interbedded sandstone, shale, and limestone usually characterized by ledgy outcrops. Orange to reddish sandstone forms cliffs near Sedona. This unit includes Supai Group and Hermit Shale in northern Arizona and Naco Group in southern Arizona. It was deposited in coastal-plain to shallow-marine settings during time of variable and changing sea level. Rocks of this map unit in southern Arizona may be in part equivalent to Permian rocks of map unit P in central and northern Arizona. (280-310 Ma)
Sedimentary rocks of the Late Cretaceous Mesaverde Group (Late Cretaceous)
Gray to buff sandstone with interbedded shale and coal. These rocks, which are similar to slightly younger rocks that form Mesa Verde in southwestern Colorado, were deposited on the margin of a shallow sea. Rocks of this map unit host the only large coal deposits in Arizona. (84-88 Ma)

California

Colorado

Animas Fm (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary)
Arkosic sandstone, shale, and conglomerate; contains abundant volcanic materials; Upper Cretaceous volcaniclastic McDermott Member at base
Belden Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Shale, limestone, and sandstone. Includes Kerber Fm in south-central
Carlile Shale, Greenhorn Limestone, and Graneros Shale (Phanerozoic | Mesozoic | Cretaceous)
Chinle, Moenkopi, and Park City Fms (Phanerozoic | Paleozoic Mesozoic | Permian Triassic)
Red and gray siltstone, shale, and sandstone
Coalmont Fm (Phanerozoic | Cenozoic | Tertiary)
Arkosic sandstone, conglomerate, and shale; coal in lower part; in North Park
Colorado Group (Phanerozoic | Mesozoic | Cretaceous)
Consists of Niobrara Formation (Kn) and either Benton Shale or Carlile, Greenhorn, and Graneros Fms (Kcg)
Cuchara Fm (Phanerozoic | Cenozoic | Tertiary)
Sandstone and shale
Dakota and Morrison Fms (Phanerozoic | Mesozoic | Jurassic Cretaceous)
Dakota, Burro Canyon, Morrison, and Junction Creek Fms (Phanerozoic | Mesozoic | Jurassic Cretaceous)
Burro Canyon is locally absent
Dakota Sandstone and Burro Canyon Fm (Phanerozoic | Mesozoic | Cretaceous)
Sandstone, shale, and conglomerate. In northwest and west-central: Lower Cretaceous. In southwest: Lower and Upper Cretaceous.
Dakota Sandstone and Purgatoire Fm (Phanerozoic | Mesozoic | Cretaceous)
Sandstone and shale
Denver Fm or lower part of Dawson Arkose (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary)
Arkosic sandstone, shale, mudstone, conglomerate, and local coal beds
Dolores Fm (Phanerozoic | Mesozoic | Triassic)
Red siltstone, shale, sandstone, and limestone-pellet conglomerate
Eagle Valley Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Siltstone, shale, and local gypsum
Eagle Valley Fm - evaporitic facies (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Gypsum, siltstone, and shale; salt present in deep borings. Intertongues with Minturn and Lower Maroon Fms. Diapiric structure in many places
Evaporitic facies of Minturn And Belden Fms in South Park and southward (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Gypsum, siltstone, and shale
Fort Union Fm (Phanerozoic | Cenozoic | Tertiary)
Shale, sandstone, and local coal beds
Frontier Sandstone and Mowry Shale Members of Mancos Shale, and Dakota Sandstone (Phanerozoic | Mesozoic | Cretaceous)
Locally includes, at base, Burro Canyon Fm (shale and sandstone) or, in western Moffat County, Cedar Mountain Fm (conglomerate and shale)
Glen Canyon Group and Chinle Fm (Phanerozoic | Mesozoic | Triassic Jurassic)
In southwest, Glen Canyon Group consists of Navajo Sandstone, Kayenta Fm (red siltstone, shale, and sandstone) and Wingate Sandstone; Chinle is red siltstone
Green River Fm (Phanerozoic | Cenozoic | Tertiary)
Marlstone, sandstone, and oil shale
Green River Fm--Lower Part (Phanerozoic | Cenozoic | Tertiary)
Shale, sandstone, marlstone, and limestone in Anvil Points, Garden Gulch, and Douglas Creek Members; in Piceance basin
Green River Fm--Luman Tongue (Phanerozoic | Cenozoic | Tertiary)
Carbonaceous shale and marlstone; in Sand Wash basin
Green River Fm--Parachute Creek Member (Phanerozoic | Cenozoic | Tertiary)
Parachute Creek Member--Oil shale, marlstone, and siltstone; in Piceance basin
Hermosa Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Arkosic sandstone, conglomerate, shale, and limestone; gypsum and salt in Paradox Member present in salt anticlines near Utah border
Huerfano Fm (Phanerozoic | Cenozoic | Tertiary)
Shale and sandstone. Includes Farisita Conglomerate in northwestern Huerfano County
Hunter Canyon Fm (Phanerozoic | Mesozoic | Cretaceous)
Sandstone and shale
Iles Fm (Phanerozoic | Mesozoic | Cretaceous)
Sandstone and shale. Trout Creek Sandstone Member at top; coal beds in upper half
Kayenta Fm, Wingate Sandstone, and Chinle Fm (Phanerozoic | Mesozoic | Triassic)
Kayenta Fm: red siltstone, shale, and sandstone. Chinle Fm: red siltstone and sandstone
Kirtland Shale and Fruitland Fm (Phanerozoic | Mesozoic | Cretaceous)
Shale, sandstone, and major coal beds
Lance Fm (Phanerozoic | Mesozoic | Cretaceous)
Shale, sandstone, and minor coal beds; Fox Hills equivalent at base
Laramie Fm (Phanerozoic | Mesozoic | Cretaceous)
Shale, claystone, sandstone, and major coal beds
Leadville, Gilman, Dyer, Parting, and Sawatch Fms in west-central and south-central. Leadville Limestone, Ouray Limestone, Elbert Fm, and Ignacio Quartzite in far southwest (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian(?) Devonian(?) Carboniferous)
Elbert Fm: shale and sandstone.
Leadville Limestone, Gilman Sandstone, Dyer Dolomite, and Parting Fm (Phanerozoic | Paleozoic | Ordovician Silurian(?) Devonian)
Parting Fm: quartzite and shale.
Lewis Shale (Phanerozoic | Mesozoic | Cretaceous)
Lodore Fm (Phanerozoic | Paleozoic | Cambrian)
Sandstone, shale, and conglomerate
lower part of Green River Fm and Wasatch Fm (Phanerozoic | Cenozoic | Tertiary)
Shale and sandstone
Lykins Fm (Phanerozoic | Paleozoic Mesozoic | Permian Triassic)
Red siltstone, shale, and limestone
Madison Limestone (Phanerozoic | Paleozoic | Carboniferous Mississippian)
Upper part includes equivalents of Upper Mississippian Doughnut and Humbug Fms (shale, limestone, and sandstone)
Madison Limestone and Lodore Fm (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian(?) Devonian(?) Carboniferous)
Mancos Shale (Phanerozoic | Mesozoic | Cretaceous)
Intertongues complexly with units overlying Mesaverde Group or Formation; lower part consists of a calcareous Niobrara equivalent and Frontier Sandstone and Mowry Shale Members; in areas where the Frontier and Mowry Members (Kmfm), or these and the Dakota Sandstone (Kfd) are distinguished, map unit (Km) consists of shale above Frontier Member
Mancos Shale--Frontier Sandstone and Mowry Shale Members (Phanerozoic | Mesozoic | Cretaceous)
Frontier Sandstone and Mowry Shale Members and intervening shale zone
Mancos Shale--Juana Lopez Member (Phanerozoic | Mesozoic | Cretaceous)
Calcareous sandstone; a thin but persistent unit distinguished only locally
Menefee Fm and Point Lookout Sandstone (Phanerozoic | Mesozoic | Cretaceous)
sandstone, shale, and coal; sandstone
Mesaverde Fm, undivided (Phanerozoic | Mesozoic | Cretaceous)
In northwest and west-central: Major coal beds in lower part; Rollins Sandstone Member at base in Delta, Gunnison, and Pitkin Counties. In southwest: sandstone and shale.
Mesaverde Group or Fm--Lower part (Phanerozoic | Mesozoic | Cretaceous)
Sandstone, shale, and major coal beds
Mesaverde Group or Fm--Upper part (Phanerozoic | Mesozoic | Cretaceous)
In Moffat and Rio Blanco Counties, sandstone, shale, and coal beds above Sego Sandstone. Along Grand Hogback south of Colorado River, sandstone and shale above coal-bearing sequence
Minturn and Belden Fms (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Minturn Fm in west-central and south-central and other units (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Arkosic sandstone, conglomerate, shale, and limestone. Includes Madera Fm and Sharpsdale Fm of Chronic (1958) in Sangre de Cristo Range and Gothic Fm of Langenheim (1952) in Elk Mountains. Other units of Middle Pennsylvanian age.
Morgan Fm and Round Valley Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Morgan Fm: limestone, sandstone, and shale. In far northwest.
Mount Garfield Fm and Sego Sandstone (Phanerozoic | Mesozoic | Cretaceous)
Sandstone and shale; major coal beds in lower part of Mount Garfield
Nacimiento Fm (Phanerozoic | Cenozoic | Tertiary)
Shale and sandstone
Niobrara Fm (Phanerozoic | Mesozoic | Cretaceous)
Calcareous shale and limestone
Oligocene sedimentary rocks (Phanerozoic | Cenozoic | Tertiary)
Northwest: includes Duchesne River Fm (sandstone and shale; includes some rocks of Eocene age) and Bishop Conglomerate near Utah border. South-central: includes Florissant Lake Beds (tuffaceous shale and tuff) and Antero Fm (lime
Parting, Fremont, and Harding Fms (Phanerozoic | Paleozoic | Ordovician Silurian(?) Devonian)
Pictured Cliffs Sandstone and Lewis Shale (Phanerozoic | Mesozoic | Cretaceous)
Pierre Shale (Kp), Niobrara (Kn), and Carlile, Greenhorn, and Graneros (Kcg) Fms, undivided (Phanerozoic | Mesozoic | Cretaceous)
Pierre Shale--Lower unit (Phanerozoic | Mesozoic | Cretaceous)
Sharon Springs Member (organic-rich shale and numerous bentonite beds) in lower part
Pierre Shale--Middle unit (Phanerozoic | Mesozoic | Cretaceous)
In Boulder-Fort Collins area, contains Richard, Larimer, Rocky Ridge, Terry, and Hygiene Sandstone Members; elsewhere shale between zones of Baculites reesidei and B. scotti
Pierre Shale, undivided (Phanerozoic | Mesozoic | Cretaceous)
Pierre Shale--Upper unit (Phanerozoic | Mesozoic | Cretaceous)
Poison Canyon Fm (Phanerozoic | Cenozoic | Tertiary)
Arkosic conglomerate, sandstone, and shale
Rico and Hermosa Fms (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Arkosic sandstone, conglomerate, shale, and limestone. Includes at base in some areas siltstone and shale of Molas Fm or Larsen Quartzite
San Jose Fm (Phanerozoic | Cenozoic | Tertiary)
Siltstone, shale, and sandstone
Sego Sandstone, Buck Tongue of Mancos Shale, and Castlegate Sandstone (Phanerozoic | Mesozoic | Cretaceous)
South Park Fm (Phanerozoic | Cenozoic | Tertiary)
Arkosic sandstone and shale, volcaniclastic conglomerate, and andesite flows and breccia
Triassic and Permian rocks (Phanerozoic | Paleozoic Mesozoic | Permian Triassic)
Red siltstone, shale, and sandstone. Includes various combinations of Nugget, Jelm, Popo Agie, Chugwater, Red Peak, Forelle, Satanka, and Goose Egg Fms near Wyoming border
Uinta Mountain Group (Proterozoic | Mesoproterozoic)
Quartzite, conglomerate, and shale
Upper part of Dawson Arkose (Phanerozoic | Cenozoic | Tertiary)
Arkosic sandstone, conglomerate, and shale. Includes Green Mountain Conglomerate south of Golden
Vermejo Fm and Trinidad Sandstone (Phanerozoic | Mesozoic | Cretaceous)
Shale, sandstone, and major coal beds; sandstone
Wasatch Fm (Phanerozoic | Cenozoic | Tertiary)
Claystone, shale, and sandstone
Wasatch Fm (including Fort Union equivalent at base) and Ohio Creek Fm (Phanerozoic | Cenozoic | Tertiary)
Claystone, mudstone, sandstone, and conglomerate
Wasatch Fm--Niland Tongue (Phanerozoic | Cenozoic | Tertiary)
Mudstone, sandstone, and carbonaceous shale; in Sand Wash basin
Williams Fork Fm (Phanerozoic | Mesozoic | Cretaceous)
Sandstone, shale, and major coal beds

Connecticut

East Berlin Formation (Lower Jurassic)
East Berlin Formation - Maroon siltstone, silty and sandy shale, and fine-grained silty sandstone, generally well laminated and commonly well indurated, alternating with dark fissile shale; dolomitic carbonate common in cement, concretions, and thin argillaceous laminae. Local arkose; grades eastward into coarse conglomerate close to eastern border fault. The East Berlin Formation of the Hartford basin contains eight facies: trough cross-bedded sandstones, horizontally stratified sandstones, interbedded sandstones and mudrocks, ripple cross-laminated siltstones, black shales, stratified mudrocks, disrupted shales, and disrupted mudstones. These facies are interpreted as a continental depositional system and are divided into two assemblages. Sandflat/alluvial plain facies assemblage (sandstones and siltstones) is composed of sheet-flood deposits. The lacustrine assemblage (shales and mudrocks) represents a saline lake-playa system (Gierlowski-Kordesch and Rust, 1994).
Portland Arkose (Lower Jurassic)
Portland Arkose - Reddish-brown to maroon micaceous arkose and siltstone and red to black fissile silty shale. Grades eastward into coarse conglomerate (fanglomerate).
Shuttle Meadow Formation (Lower Jurassic)
Shuttle Meadow Formation - Maroon to dark-gray, silty shale, siltstone, and fine-grained silty sandstone, generally well and thinly laminated. In the southern part of the State includes a layer, up to 5 m thick, of blue, commonly sandy, fine-grained limestone or dolomitic limestone, grading laterally into calcareous siltstone. Coarser and more arkosic to east and south, grading into conglomerate near the eastern border fault.

Georgia

Chickamauga Group; Middle Ordovician rocks; Athens Shale (Middle Ordovician)
Chickamauga Group; Middle Ordovician rocks; includes the Athens Shale (Oa)
Chilhowee Formation (Cambrian)
Chilhowee Formation, includes Weisner Formation of Kesler, 1950
Conasauga Group; Lower unit; shale and sandstone unit (Cambrian)
Conasauga Group; Lower unit; shale and sandstone unit: Includes shale and sandstone unit (Ccs) with lower dolostone unit (Ccdl). Possible equivalent of Pumpkin Valley Shale of Tennessee
Conasauga Group; Middle unit; Shale unit (Cambrian)
Conasauga Group; Middle unit; Shale unit: Includes limestone unit (Ccls), possible equivalent of Rutledge Limestone of Tennessee and shale unit (Cc), possible equivalent of Rogersville Shale of Tennessee
Conasauga Group; Upper unit; limestone and shale unit (Cambrian)
Conasauga Group; Upper unit; limestone and shale unit: Includes limestone and shale unit (Ccsl). Possible equivalent of the Maryville Limestone and Nolichucky Shale of Tennessee with a dolostone member (Ccd).
Floyd Shale (Mississippian)
Floyd Shale (Mfs): includes the Hartselle Sandstone Member (Mh) in Floyd County and an unnamed limestone member (Ml in Floyd County) at the base
Floyd Shale; unnamed limestone member (Mississippian)
Floyd Shale; unnamed limestone member (Ml in Floyd County) at the base
Fort Payne Shale; Lavender Shale Member (Mississippian)
Fort Payne Shale (Mfp) with Lavender Shale Member (Mls)
Lookout Sandstone; Gizzard Formation (Pennsylvanian)
Lookout Sandstone; Gizzard Formation
Mississippian undifferentiated (Mississippian)
Mississippian undifferentiated: Includes Pennington Shale, Bangor Limestone (except in Floyd County), Hartselle Sandstone, Golconda Formation, Gasper Limestone, Ste. Genevieve Limestone and St. Louis Limestone
Pennsylvanian undifferentiated (Pennsylvanian)
Pennsylvanian undifferentiated
Red Mountain Formation (Silurian)
Red Mountain Formation
Rome Formation (Cambrian)
Rome Formation

Iowa

Cherokee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Des Moines])
Cyclic deposits with carbonaceous shale, clay, siltstone, with lesser sandstone, and thick coal beds; minor but persistent limestone beds; may include parts of Atoka or Morrow Series.
Colorado and Dakota Groups (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Middle(?) Cretaceous-Late)
Sandstone and shale with minor limestone; includes Carlile, Greenhorn, Graneros, and Dakota FMs. Full section present in only the extreme NW part of Iowa; in southern and easternmost areas only Dakota is present.
Cretaceous Undifferentiated (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Middle(?) Cretaceous-Late)
Variably calcareous, serverely deformed shales, minor sandstone and carbonate rock; in Manson anomalous area only
Douglas Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgil])
Cyclic deposits with shale, siltstone and minor thin limestone beds; Lawrence Formation at top and Stranger Formation at base.
Ft. Dodge Beds (Phanerozoic | Mesozoic | Jurassic)
Gypsum and red and green shale; in Webster CO only
Galena-Decorah-Platteville Formations (Phanerozoic | Paleozoic | Ordovician-Middle [Mohawkian])
Galena FM- dolomite, minor limestone; chert in lower half. Approx thickness 230 ft. Decorah FM- brown limestone and dolomite; gray-green and brown shales at top and base. Approx thickness 60 ft. Platteville FM- fossiliferous gray limestone and brown dolomite; grayish-green shale at base (Glenwood). Fine- to medium-grained sandstone occurs above the Glenwood in the subsurface of southeastern Iowa. Approx thickness 110 ft
Kansas City Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missouri])
Cyclic deposits with prominent limestone beds, shale; Bonner Springs Shale at top and Hertha Limestone at base.
Lansing Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missouri])
Cyclic deposits with thin bedded limestones and interbedded red and green shales; Stranton Limestone at top, Vilsa Shale and Plattsburg Limestone at base.
LaPort City Chert (Phanerozoic | Paleozoic | Devonian-Early)
Predominantly chert with limestone and dolomite; minor shale and sandstone. Found in subsurface only.
Lime Creek Formation (Phanerozoic | Paleozoic | Devonian-Late)
Fossiliferous limestone or dolomite in upper part with local stromatoporoid biostromes in north-central Iowa; extremely fossiliferous gray shale and argillaceous limestone in middle; gray shale in lower part with spore carps toward base.
Maquoketa Formation (Phanerozoic | Paleozoic | Ordovician-Late [Cincinnatian])
Predominantly grayish-green shale in east-central area; predominantly brown dolomite and chert in the subsurface of north-central and western areas; red shale with limonite or hematite pellets (Neda) occurs locally at top.
Marmaton Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Des Moines])
Alternating shale and limestone, with some sandstone and coal; Lenapah FM at top and Fort Scott at base.
Meramec Series (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late)
Ste. Genevieve Limestone- fossiliferous limestone and red and green shale. Approx. thickness 50 ft. St. Louis Limestone- limestone and dolomite, sandstone locally perdominant; locally contains chert. Spergen Formation- sandy micaceous dolomite.
Osage Series (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early)
Warsaw Formation- gray, dolomitic shale and argillaceous dolomite; chalcedonic chert. Locally contains many geodes.Approx thickness 85 ft. Keokuk Limestone- fossiliferous, gray or brown limestone and dolomite; gray and brown chert with white spicules, locally predominant in lower portion; minor brown or gray shale. Approx thickness 90 ft. Burlington Limestone- gray, fossiliferous limestone and darker gray dolomite; white and gray mottled fossiliferous chert, locally contains dolomite crystals; two widespread glauconite zones; basal sandstone locally in southeastern Iowa. Approx thickness 80 ft.
Pleasanton Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missouri])
Shale with some sandstone, thin limestone beds and minor coal; Exline Limestone near top Chariton Conglomerate at base. .
Shawnee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgil])
Cyclic deposits with prominent limestone beds and thin shales; Topeka Formation at top and Oread Formation at base.
Shell Rock Formation (Phanerozoic | Paleozoic | Devonian-Late)
Predominantly stromatoporoid biostromes in upper part; argillaceous limestone and gray shale in middle; massive limestone and dolomite in lower part with stromatoporoid biostromes near base; in north-central Iowa only.
St. Croixan Series (Phanerozoic | Paleozoic | Cambrian-Furongian)
Jordan Sandstone- fine- to medium-grained, well sorted, frosted sandstone (includes Madison Sandstone). Approx thickness 120 ft. St. Lawrence Formation- coarsely crystalline, gray, silty dolomite; glauconite common (includes Lodi Sandstone).Approx thickness 230+ ft Franconia Sandstone- glauconitic, dolomitic siltstone and shale and glauconitic sandstone. Approx thickness 280 ft Galesville Sandstone- medium- to coarse-grained, white to gray sandstone. Eau Claire Sandstone- fissile, gray, silty shale and dolomitic siltstone and fine-grained sandstone. Mt. Simon Sandstone- medium- to coarse-grained sandstone with minor shale stringers. Galesville+Eau Claire+Mt. Simon=Approx thickness 1000 ft
St. Peter Sandstone (Phanerozoic | Paleozoic | Ordovician-Early [Chazyan])
Coarse to fine, rounded, frosted sand grains; minor green shale stringers.
Wabaunsee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgil])
Cyclic deposits, principally shale with limestone, siltstone, minor sandstone units and thin coal seams.
Wapsipinicon Formation (Phanerozoic | Paleozoic | Devonian-Middle)
In descending order, finely crystalline limestone; brown dolomite with gypsum; gray, sandy shale and argillcceous limestone; and massive, finely crystalline, dolomitic limestone and pale-orange dolomite.
Yellow Spring Group (Phanerozoic | Paleozoic | Devonian-Late)
English River Formation- gray siltstone; southeastern Iowa; locally in north-central Iowa. Approx thickness 23 ft. Maple Mill Shale- greenish-gray shale, silty in upper part; contains spore carps; discoidal, concentrically laminated limonite pellets at top in the subsurface of central and southwestern Iowa. Approx thickness 300 ft. Aplington Formation- argillaceous, silty dolomite and minor chert; quartz geodes. Approx thickness 40 ft. Sheffield Formation- greenish-gray shale in central Iowa and in the subsurface of southwestern Iowa; in decending order, dusky yellowish-brown shale followed by greenish-gray shale, very light olive-gray shale, and dark olive-gray shale in the subsurface of southeastern Iowa. Approx thickness 95 ft.

Idaho

Arenite, carbonate, conglomerate, and shale; Late Proterozoic rifted continental margin; southeastern Idaho (Late Proterozoic)
Uppermost Younger Precambrian massive quartzite with carbonate beds of central and southeastern Idaho; overlies (Z1s).
Arenite, dolostone, limestone, siltstone, and shale; Cambrian marine outer continental-shelf deposits; central Idaho (Cambrian)
Cambrian thrusted quartzite, fine-grained detritus, and dolomite of central Idaho.
Arenite, shale, dolostone, siltstone, conglomerate, chert, and limestone; Lower Ordovician marine outer continental-shelf deposits; central Idaho (Early Ordovician)
Lower Ordovician dolomite, nodular cherty limestone, and intraformational conglomerate.
Chert, shale, phosphorite, and carbonates; Permian restricted marine epicontinental-basin deposits; southeastern Idaho (Permian)
Permian phosphatic sandstone, mudstone and chert of east-central Idaho.
Coralline Limestone, sandstone, siltstone, shale, chert, and phosphorite; Mississippianshallow marine inner continental-shelf deposits; east-central Idaho, central Idaho (Mississippian )
Mississippian shallow-water coralline limestone interval of southern Idaho.
Dolostone, limestone, sandstone, shale, and conglomerate; Devonian marine continental-shelf deposits; east-central and southeastern Idaho (Devonian)
Devonian bedded dolomite and limestone interval of eastern and southern Idaho.
Dolostone, quartzite, shale, and limestone; Upper to Middle Ordovician marine continental-shelf deposits; east central Idaho (Late and Middle Ordovician)
Upper and Middle Ordovician dolomite and quartzite unconformably overlying (Ol).
Dolostone, shale, and chert; Silurian marine inner continental-shelf deposits (Late and Middle Silurian)
Upper and Middle Silurian fossiliferous dolomite; clay, silt and sand near base.
Dolostone, shale, arenite, siltstone, limestone, conglomerate, and chert; Ordovician and Cambrian marine outer continental-shelf deposits; central Idaho (Ordovician and Cambrian)
Ordovician and Cambrian thrusted dolomite, siltstone, and quartzite of central Idaho.
Limestone, arenite, and shale; Cambrian marine continental-shelf deposits; northern Idaho (Middle Cambrian)
Middle Cambrian thinly laminated claystone overlying coarse-grained pebbly quartzite of northern Idaho.
Limestone, arenite, dolostone, chert, siltstone, shale; Upper Paleozoic marine continental-shelf deposits; southeastern Idaho (Late Paleozoic)
Upper Paleozoic marine sediments in southern Idaho.
Limestone, arenite, shale, dolostone, and siltstone; Upper Proterozoic to Cambrian marine continental-shelf deposits; southeastern Idaho (Cambrian)
Cambrian marine dolomite, limestone, claystone, and quartzite; grades into Precambrian.
Limestone, dolostone, arenite, shale, and siltstone; Lower Paleozoic marine continental-shelf deposits; southeastern Idaho; (Early Paleozoic)
Lower Paleozoic marine carbonate and clastic units southeast of the Snake Plain.
Limestone, dolostone, shale, and arenite; Ordovician and Cambrian shallow marine inner continental-shelf deposits; southeastern Idaho (Ordovician and Cambrian)
Ordovician, commonly Lower, and Cambrian marine sediments of eastern and southern Idaho.
Limestone, sandstone, dolostone, and chert; Permian to Pennsylvanian marine epicontinental-basin deposits; southeastern Idaho; (Early Permian to Early Pennsylvanian)
Lower Permian to Lower Pennsylvanian chert, limestone, and sandstone of southern Idaho; subdivisions are (Ps, and PNs).
Limestone, sandstone, shale, and chert; Pennsylvanian marine epicontinental-basin deposits; southeastern Idaho (Pennsylvanian)
Pennsylvanian beds; lowermost portion of the southern Idaho sequence (PPNs).
Limestone, shale, siltstone, chert, and conglomerate; Mississippian western turbiditic flysch to eastern shallow-water carbonates; east-central Idaho (Mississippian)
Mississippian shallow-water carbonate-to-clastic sequence of east-central Idaho.
Limestone, slate; Upper Triassic greenschist-facies metamorphic rocks; western Idaho, Blue Mountains island-arc complex; (Late Triassic)
Upper Triassic shale overlying reefal limestone and dolomite in west-central Idaho.
Sandstone, conglomerate, siltstone, tuff, claystone, limestone, and diatomite; Pliocene tuffaceous alluvial and lacustrine deposits; Snake River Plain and vicinity, southeastern Idaho (Pliocene )
Pliocene stream and lake deposits; may be due to volcanic and block-faulting events.
Sandstone, limestone, and shale; Upper Triassic marine to non-marine epicontinental deposits; southeastern Idaho (Late Triassic)
Upper Triassic shallow-marine to non-marine sediments; oxidized shale, siltstone, limestone, and conglomeratic sandstone of eastern Idaho.
Sandstone, limestone, siltstone, shale, and conglomerate; Lower Permian to Middle Pennsylvanian deltaic turbidites; central Idaho; (Early Permian)
Lower Permian to Middle Pennsylvanian thrusted, marine detritus of central Idaho.
Sandstone, shale, siltstone, limestone, and coal; Late Cretaceous Cordilleran retroarc-foreland-basin deposits; southeastern Idaho (Late Cretaceous)
Upper Cretaceous thick detrital and fresh-water limestone beds of southeastern Idaho.
Sandstone, siltstone, shale, limestone, and coal ; Early Cretaceous Cordilleran retroarc-foreland-basin deposits; southeastern Idaho (Early Cretaceous)
Lower Cretaceous shale, siltstone, red-bed sandstone and fresh-water limestone.
Shale, arenite, conglomerate, intermediate and felsic volcanic rocks; Late Proterozoic rifted continental margin; southeastern Idaho (Late Proterozoic)
Younger Precambrian volcanic and diamictic units of central and southeastern Idaho.
Shale, arenite, siltstone, limestone, and chert; thrust-bounded Devonian to Ordovician deep-marine-basin deposits; central Idaho (Devonian and Silurian)
Devonian and Silurian thrusted, deep-water argillite beds of central Idaho.
Shale, conglomerate, sandstone, siltstone, limestone, and chert; Mississippian turbidite flysch from a western source; central Idaho (Mississippian)
Mississippian thrusted, shallow-to-deep marine detrital units of central Idaho.
Shale, limestone, and sandstone; Triassic marine to non-marine epicontinental deposits (subunits are TRl and TRu) (Triassic)
Triassic shallow-marine to non-marine sediments of eastern Idaho; subdivisions are (TRu and TRl).
Siltstone, evaporites, and redbeds; Late Jurassic Cordilleran retroarc-foreland-basin deposits; southeastern Idaho (Late Jurassic)
Upper Jurassic shallow-marine to non-marine sediments; glauconitic and variegated sandstone, siltstone and oolitic limestone of eastern Idaho.
Siltstone, shale, and limestone; Early Triassic marine to non-marine epicontinental deposits; southeastern Idaho (Early Triassic)
Lower Triassic shallow-marine to non-marine sediments; limestone and chert above shaley sandstone, siltstone, and limestone of eastern Idaho.
Siltstone, shale, sandstone, and limestone; Jurassic Cordilleran retroarc-foreland-basin deposits (subunits are Jl and Ju); southeastern Idaho (Jurassic)
Jurassic shallow-marine to non-marine sediments of eastern Idaho; subdivisions are (Jl and Ju).
Tuffaceous shale, sandstone, conglomerate, and lignite; Eocene to Pliocene alluvial and lacustrine deposits; central and southern Idaho (Tertiary)
Tertiary continental sediments; predominantly Upper Tertiary in age; subdivisions are:(Tpd, Tmd, and Ted).

Illinois

Indiana

Antrim Shale (Devonian)
Antrim Shale - Black shale; gray shale and limestone in lower part
Bond Formation (Pennsylvanian)
Bond Formation - Mostly shale and sandstone; also includes thin beds of limestone and coal
Buffalo Wallow Group (Mississippian)
Buffalo Wallow Group - Mostly shale and sandstone; also includes thin beds of micritic limestone. L, Leopold Limestone member
Carbondale Group (Pennsylvanian)
Carbondale Group - Mostly shale and sandstone; also includes thin beds of limestone, clay, and coal. S, Springfield Coal Member
Coldwater Shale (Mississippian)
Coldwater Shale - Mostly gray shale
Dillsboro Formation (Ordovician)
Dillsboro Formation - Skeletal limestone and calcareous shale
Ellsworth Shale (Devonian-Mississippian)
Ellsworth Shale - Green shale; some black shale in lower part
Kope Formation (Ordovician)
Kope Formation - Shale and thin skeletal limestone
Maquoketa Group (Ordovician)
Maquoketa Group - Shale and limestone
Mattoon Formation (Pennsylvanian)
Mattoon Formation - Mostly shale and sandstone; also includes thin beds of coal
Munising Group (Cambrian)
Munising Group - Shale, sandstone, limestone, and dolomite
New Albany Shale (Devonian-Mississippian)
New Albany Shale - Black and greenish-gray shale
Patoka and Shelburn Formations (Pennsylvanian)
Patoka and Shelburn Formations - Mostly shale and sandstone; also includes thin beds of limestone and coal. WF, top of West Franklin member
Raccoon Creek Group (Pennsylvanian)
Raccoon Creek Group - Mostly shale and sandstone; also includes thin beds of limestone, clay, and coal. B, Buffaloville Coal Member; LB, Lower Block Coal Member
Salamonie Dolomite, Cataract Formation, and Brassfield Limestone (Silurian)
Salamonie Dolomite, Cataract Formation, and Brassfield Limestone
Stephensport Group (Mississippian)
Stephensport Group - Sandstone, micritic and skeletal limestone, and shale
West Baden Group (Mississippian)
West Baden Group - Shale, sandstone, and micritic and skeletal limestone
Whitewater Formation (Ordovician)
Whitewater Formation - Skeletal limestone and calcareous shale; dolomitic mudstone (S, Saluda Member) at base

Kansas

Admire Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late)
Includes: Grenola Limestone, Roca Shale, Red Eagle Limestone (base RE), Johnson Shale, Foraker Limestone (base FO), Janesville Shale with Five Point Limestone Member (base FP), Falls City Limestone, and Onaga Shale.
Carlile Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
chalky shale with bentonite and thick chalk beds, dark gray fissile shale containing septarian concretions, and fine-grained sandstone.
Chase Group (Phanerozoic | Paleozoic | Permian [Gearyan])
Nolans Limestone- upper and lower limestone separated by shale, 40 ft thick. Odell Shale- mostly red and green shale, 40 ft. thick. Winfield Limestone (base WF)- cherty limestone with fossiliferous gray shale, 25 ft. thick. Doyle Shale- two shale members separated limestone, 70 ft. thick. Barneston Limestone (base BA)- two thick limestone members separated by thin limestone, 90 ft. thick: with Fort Riley Limestone Member( base FR)- gray to tan massive to thin bedded limestone with minor gray shale, 45 ft thick. Matfeild Shale- two varicolored shale members separated by limestone, 80 ft. thick. Wreford Limestone- two cherty limestone members separated shale, 40 ft. thick.
Cherokee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early [Desmoinesian])
Includes: Cabaniss FM (base CA) with Verdigris Limestone Member (base V) and Mineral coal bed (base MC), Krebs FM with Bluejacket Sandstone Member (base BJ) and Warner Sandstone Member (base WR).
Council Grove Group (Phanerozoic | Paleozoic | Permian [Gearyan])
Includes: Speiser Shale, Funston Limestone, Blue Rapids Shale, Crouse Limestone (base CS), Easy Creek Shale, Bader Limestone (base BE), Stearns Shale, Beattie Limestone, Eskridge Shale, and Neva Limestone.
Dakota Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
White, gray, red, brown and tan kaolinitic claystone, mudstone, shale and siltstone interbedded with grayish to yellowish brown thick lenticular sandstone beds. It also contains lignite and sandstone is commonly well cemented with iron oxide and calcite.
Dockum Group (Phanerozoic | Mesozoic | Triassic)
varicolored shales and red sandstone
Douglas Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgilian])
Lawrence FM (base LA)- mostly gray shale and sandstone with minor red shale, coal, gray limestone and conglomerate, thickness ranges from 140ft to 250 ft. Stranger FM- five members containing sandstone, shale, and minor limestone, coal and conglomerate ranging from 100 ft. to 180 ft. thickness.
Greenhorn Limestone and Graneros Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Greenhorn FM- thin bedded gray, chalky limestone and calcareous shale. Graneros Shale- fissile, noncalcareous, gray shale locally contains sandstone and siltstone beds.
Guadalupia Series: Big Basin Formation, Day Creek Dolomite, and Whitehorse Formation (Phanerozoic | Paleozoic | Permian [Custerian Cimarronian])
Big Basin FM- red silty shale, siltstone, dolomitic siltstone and fine-grained feldspathic sandstone. Day Creek Dolomite- light gray to pink, dense, fine-grained dolomite. Whitehorse FM- mostly red beds of feldspathic sandstone with some beds of siltstone and shale and minor dolomite.
Kansas City Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Missourian])
Includes: Lane Shale,Wyandotte Limestone (base WY), Liberty Memorial Shale, Iola Limestone (base I), Chanute Shale (base CH), Dewey Limestone, Nellie Bly FM, Cherryvale FM, Dennis Limestone (base DN), Galeburg Shale, Mound Valley Limestone, Ladore Shale, Swope Limestone (base SW), Elm Branch Shale, Hertha Limestone.
Kiowa Shale and Cheyenne Sandstone (Phanerozoic | Mesozoic | Cretaceous-Early)
Kiowa Shale or FM- light -gray to black illitic shale with thin coquinoidal limestone beds at the base; sandstone lenses common. Cheyenne Sandstone- massive to crossbedded, light-gray to buff fine-grained sandstone with lenses of gray sandy shale and conglomerate.
Lansing Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Missourian])
Stanton Limestone- three limestone and two shales members, ranges from 15 to 130 ft. thick. Vilas Shale- sandy, carbonaceous gray shale with some sandstone and limestone locally, ranges from 5 to 120 ft. thick. Plattsburg Limestone- two limestone members separated by shale, ranging from 25 to 115 ft. thick.
Marmaton Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early [Desmoinesian])
Includes: Lost Branch FM, Memorial Shale, Lenapah Limestone (base LE), Nowata Shale, Altamont Limestone (base PA), Bandera Shale, Pawnee Limestone (base PA), Labette Shale and Fort Scott Limestone.
Niobrara Chalk (Phanerozoic | Mesozoic | Cretaceous-Late)
interbedded, soft, light-gray calcareous shale and chalk
Nippewalla Group (Phanerozoic | Paleozoic | Permian [Custerian Cimarronian])
Dog Creek FM- maroon silty shale, siltstone, fine-grained feldspathic sandstone. Blaine FM- (base B) gypsum beds separated by dolomite and red shale. Flower Pot Shale -(base FL) red gypsiferous shale silty shale and minor sandstone and siltstone. Cedar Hills Sandstone- feldspathic sandstone, siltstone, and silty shale. Salt Plain FM- red flaky, silty shale and some siltstone with thick salt beds at base. Harper Sandstone with Kingman Sandstone member (base K)- red argillaceous siltstone and fine silty sandstone with a few beds of res shale and white sandstone. Stone Coral FM- dolomite, anhydrite, gypsum and salt.
Pierre Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
thin bedded gray to brownish gray shale; contains concretions, selenite crystals, thin beds of bentonite and locally chalky beds.
Pleasanton Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Missourian])
Includes: Shale Hill FM (base SH), and Hepler FM. Chiefly gray to very dark gray or yellowish gray shale with sandstone members and some limestone and coal.
Shawnee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgilian])
Includes: Topeka Limestone, Calhoun Shale, Deer Creek Limestone (base DC), Tecumseh Shale, Lecompton Limestone (base LC), Kanwaka Shale, Oread Limestone with Plattsmouth Limestone Member (base PL).
Sumner Group (Phanerozoic | Paleozoic | Permian [Cimarronian])
Ninnescah Shale (base N)- mostly red silty shale with some gray shale , argillaceous limestone and dolomite. Wellington FM with Carlton Limestone Member (base CR)-mostly gray and some red shale with minor limestone and dolomite, siltstone, gypsum and anhydrite
Wabaunsee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgilian])
Includes: Wood Siding FM, Root Shale, Stotler Limestone (base ST), Pillsbury Shale, Zeandale Limestone (base Z), Willard Shale, Emporia Limestone (base E), Auburn Shale, Bern Limestone (base BR), Scranton Shale, Howard Limestone (base H), and Severy Shale.

Kentucky

Ashlock Formation, Grant Lake and Calloway Creek Limestones, and Fairview Formation, undivided (Ordovician)
Ashlock Formation, Grant Lake and Calloway Creek Limestones, and Fairview Formation, undivided
Breathitt Formation, lower part (Pennsylvanian)
Breathitt Formation, lower part; lower part which includes Livingston Conglomerate Member of Lee Formation in eastern Rockcastle County
Breathitt Formation, middle part (Pennsylvanian)
Breathitt Formation, middle part
Bull Fork Formation (Ordovician)
Bull Fork Formation
Bull Fork Formation and Grant Lake and Calloway Creek Limestones, undivided (Ordovician)
Bull Fork Formation and Grant Lake and Calloway Creek Limestones, undivided; Along Ohio River in Oldham and Trimble Counties
Carbondale Formation (Middle Pennsylvanian)
Carbondale Formation
Caseyville Formation (Lower to Middle Pennsylvanian)
Caseyville Formation
Clayton and McNairy Formations, undivided (Paleocene to Upper Cretaceous)
Clayton and McNairy Formations, undivided
Crab Orchard Formation and Brassfield Dolomite, undivided (Silurian)
Crab Orchard Formation and Brassfield Dolomite, undivided; locally includes Bisher Dolomite in Estill County
Cumberland Formation and Leipers and Catheys (?) Limestones, undivided (Ordovician)
Cumberland Formation and Leipers and Catheys (?) Limestones, undivided; in southernmost Kentucky
Drakes Formation (Ordovician)
Drakes Formation
Drakes Formation and Grant Lake and Calloway Creek Limestones, undivided (Ordovician)
Drakes Formation and Grant Lake and Calloway Creek Limestones, undivided; in Boyle, Casey, and Marion Counties
Garrard Siltstone and Kope and Clays Ferry Formations, undivided (Ordovician)
Garrard Siltstone and Kope and Clays Ferry Formations, undivided
High Bridge Group (Ordovician)
High Bridge Group
Jackson and Claiborne Formations, undivided (Tertiary)
Jackson and Claiborne Formations, undivided; includes some rocks of Oligocene age
Laurel Dolomite, Osgood Formation, and Brassfield Dolomite, undivided (Silurian)
Laurel Dolomite, Osgood Formation, and Brassfield Dolomite, undivided
Lee Formation (Mississippian to Pennsylvanian )
Lee Formation
Lexington Limestone (Ordovician)
Lexington Limestone
Louisville Limestone and Waldron Shale, undivided (Silurian)
Louisville Limestone and Waldron Shale, undivided
Monongahela and Conemaugh Formations, undivided (Pennsylvanian)
Monongahela and Conemaugh Formations, undivided
Pennington Formation and Newman Limestone (Mississippian)
Pennington Formation and Newman Limestone; includes Carter Caves Sandstone in Carter County and vicinity
Pennington Formation, Newman Limestone, Fort Payne Chert, Grainger Formation, Sunbury Shale, Berea Sandstone, and Bedford Shale, undivided; Pennington Formation locally includes sandstone tongue of Lee Formation (Devonian to Pennsylvanian)
Pennington Formation, Newman Limestone, Fort Payne Chert, Grainger Formation, Sunbury Shale, Berea Sandstone, and Bedford Shale, undivided; Pennington Formation locally includes sandstone tongue of Lee Formation
Pennington Formation (Paragon Formation), Bangor Limestone, Hartselle Formation, and Kidder Limestone Member of Monteagle Limestone, undivided (Mississippian)
Pennington Formation (Paragon Formation), Bangor Limestone, Hartselle Formation, and Kidder Limestone Member of Monteagle Limestone, undivided
Preachersville Member of Drakes Formation and Bull Fork Formation, undivided (Ordovician)
Preachersville Member of Drakes Formation and Bull Fork Formation, undivided; in Bath and Montgomery Counties
Renfro and Muldraugh Members of Borden Formation and Fort Payne Formation, undivided (Mississippian)
Renfro and Muldraugh Members of Borden Formation and Fort Payne Formation, undivided
Rocks of Chesterian age, lower part (Upper Mississippian)
Rocks of Chesterian age, lower part
Rocks of Chesterian age, upper part (Upper Mississippian)
Rocks of Chesterian age, upper part
Sturgis Formation (Middle to Upper Pennsylvanian)
Sturgis Formation
Wilcox Formation (Eocene)
Wilcox Formation
Wildie, Nada, Halls Gap, Holtsclaw Siltstone, Cowbell, Nancy, Kenwood Siltstone, New Providence Shale, Sunbury Shale, Berea Sandstone, and Bedford Shale, undivided; Borden Formation locally includes Renfro Member in eastern Kentucky (Devonian to Mississippian)
Wildie, Nada, Halls Gap, Holtsclaw Siltstone, Cowbell, Nancy, Kenwood Siltstone, New Providence Shale, Sunbury Shale, Berea Sandstone, and Bedford Shale, undivided; Borden Formation locally includes Renfro Member in eastern Kentucky

Louisiana

Massachusetts

Bellingham Conglomerate (Pennsylvanian, Cambrian or Proterozoic Z)
Bellingham Conglomerate - Red and gray metamorphosed conglomerate, sandstone, graywacke, and shale. Bellingham Conglomerate consists of conglomerate and lithic graywacke interbedded with chlorite phyllite and is confined to Bellingham basin. Also contains some volcanic rocks (rhyolite porphyry in roadcut on MA Hwy 146 at Premisy Hill west of Woonsocket, and felsite porphyry in the Franklin area east of Bellingham). Conglomerate contains pebbles of quartzite from adjacent Blackstone Group rocks and typical blue quartz of Milford Granite, so sediments are locally derived. Exposures on east side of Woonsocket Hill, southeast of Woonsocket, RI, show cliffs of steeply dipping, thin-bedded, white to gray quartzite of Blackstone Group standing above green schistose conglomerate containing many flattened white to gray quartzite pebbles and interbedded green calcareous quartz schist. Contact is probably a fault, but source of pebbles is quite obvious. In the same area, schist of Blackstone Group is difficult to distinguish from those of the Bellingham because of low-grade metamorphism of Blackstone rocks; it is probable that some of the low-grade Blackstone Rocks mapped northwest of Woonsocket in Blackstone River valley are part of Bellingham. The two rock units have been traditionally distinguished in the past by presence or absence of epidote (Warren and Powers, 1914), but this needs further study. Age is uncertain. Rocks have customarily been correlated with those of Pennsylvanian Narragansett basin; however, rocks in some exposures, such as the one at River St and Blackstone St in Woonsocket resemble Proterozoic Z Roxbury Conglomerate in Boston basin. Skehan and others (1979) suggest that Bellingham may have a similar age to that of Roxbury. This is supported by observation that Bellingham is a structural trough extending southwest from Boston basin and separating primarily Proterozoic Z granitoids from altered, but nongneissic, Proterozoic granitoids (Wones and Goldsmith, 1991). In deference to tradition, and because Proterozoic Z age has not been proven, age is shown on MA State bedrock map of Zen and others as Proterozoic Z to Pennsylvanian [map actually has age of Proterozoic Z, Cambrian, or Pennsylvanian, which differs from age stated in this report.] (Goldsmith, 1991).
East Berlin Formation (Lower Jurassic)
East Berlin Formation - Reddish-brown to pale red arkosic sandstone and siltstone, and gray sandstone, gray mudstone, and black shale; interpreted as lake beds. Assigned to Newark Supergroup (Robinson and Luttrell, 1985). The East Berlin Formation of the Hartford basin contains eight facies: trough cross-bedded sandstones, horizontally stratified sandstones, interbedded sandstones and mudrocks, ripple cross-laminated siltstones, black shales, stratified mudrocks, disrupted shales, and disrupted mudstones. These facies are interpreted as a continental depositional system and are divided into two assemblages. Sandflat/alluvial plain facies assemblage (sandstones and siltstones) is composed of sheet-flood deposits. The lacustrine assemblage (shales and mudrocks) represents a saline lake-playa system (Gierlowski-Kordesch, and Rust, 1994).
Mount Toby Formation (Lower Jurassic)
Mount Toby Formation - Reddish-brown to pale red arkosic sandstone, and gray sandstone, gray siltstone, and black shale interpreted as lake beds.
Portland Formation (Lower Jurassic)
Portland Formation - Reddish-brown to pale red arkose and siltstone, and gray sandstone, gray siltstone, and black shale interpreted as lake beds.
Rhode Island Formation (Upper and Middle Pennsylvanian)
Rhode Island Formation - Sandstone, graywacke, shale and conglomerate; minor beds of meta-anthracite. Fossil plants. Rhode Island Formation is thickest and most extensive formation in Narragansett basin. Does not extend to Norfolk basin. Consists of gray sandstone and siltstone and lesser amounts of gray to black shale, gray conglomerate, and coal beds 10 m thick. Interfingers with Wamsutta Formation in Narragansett basin. In places overlies Dedham Granite. Age is Middle and Late Pennsylvanian (Goldsmith, 1991).
Rhode Island Formation (Upper and Middle Pennsylvanian)
Rhode Island Formation - Conglomerate, sandstone, and graywacke. Rhode Island Formation is thickest and most extensive formation in Narragansett basin. Does not extend to Norfolk basin. Consists of gray sandstone and siltstone and lesser amounts of gray to black shale, gray conglomerate, and coal beds 10 m thick. Interfingers with Wamsutta Formation in Narragansett basin. In places overlies Dedham Granite. Age is Middle and Late Pennsylvanian (Goldsmith, 1991).
Shuttle Meadow Formation (Lower Jurassic)
Shuttle Meadow Formation - Reddish-brown to pale red arkosic sandstone and siltstone, and gray sandstone, gray mudstone, and black shale; interpreted as lake beds. The Shuttle Meadow Formation is assigned to Newark Supergroup and is extended into MA in the Hartford basin. It consists of sandstone strata containing one interval of gray mudstone beds. The unit grades eastward along strike into a conglomeratic facies. It overlies the New Haven Arkose or Hitchcock Volcanics and underlies the Holyoke Basalt (Robinson and Luttrell, 1985).
Sugarloaf Formation (Lower Jurassic)
Sugarloaf Formation - Reddish-brown to pale red arkose, and gray sandstone, gray siltstone, and black shale interpreted as lake beds.
Turner Falls Sandstone (Lower Jurassic)
Turner Falls Sandstone - Reddish-brown to pale red arkosic sandstone, and gray sandstone, gray siltstone, and black shale interpreted as lake beds.
Wamsutta Formation (Middle and Lower Pennsylvanian)
Wamsutta Formation - Red to pink, well-sorted conglomerate, graywacke, sandstone, and shale; fossil plants. Wamsutta Formation occurs in Narragansett and Norfolk basins. Consists of conglomerate, lithic graywacke, sandstone, and shale. Also contains rhyolite and basalt horizons near Attleboro. Northwest of Attleboro, Wamsutta overlies Diamond Hill Felsite as used by Skehan and Murray (in Skehan and others, 1979). Volcanic rocks similar to Diamond Hill Felsite crop out west of Lake Pearl, between Franklin and Wrentham, on west flank of Norfolk basin. These are shown within Wamsutta Formation on MA State bedrock map of Zen and others (1983) because of their proximity to Diamond Hill. They also resemble Proterozoic Z Mattapan Volcanic Complex. Chute (1966) described lenses of carbonate rock in red and green shale in Wamsutta in Norwood quad. Limestone also observed in rocks mapped as Wamsutta adjacent to exposed Dedham Granite at Manchester Pond Reservoir (J.P. Schafer, 1982, oral commun.). Red and green shales may actually be Cambrian. Upper member of Pondville Conglomerate grades into and interfingers with Wamsutta; in turn, Wamsutta interfingers with Rhode Island Formation in northwest part of Narragansett basin. Nonconformably overlies Dedham Granite. Partly equivalent to Rhode Island Formation. Age is Early and Middle Pennsylvanian. Contains a few plant fossils (Goldsmith, 1991).

Maryland

Allegheny Formation and Pottsville Formation (Pennsylvanian)
Allegheny Formation - Interbedded sandstone, siltstone, claystone, shale, and coal beds; Upper Freeport coal at top; where present, Brookville coal defines base; thickness 275 feet in northeast, increases to 325 feet in south and west. And Pottsville Formation - Interbedded sandstone, siltstone, claystone, shale, and coal beds; conglomeratic orthoquartzite and protoquartzite at base; thickness 60 feet in northeast, increases to 440 feet in southwest
"Chemung" Formation, Parkhead Sandstone, Brallier Formation, and Harrell Shale (Devonian)
"Chemung" Formation - Predominantly marine beds characterized by gray to olive-green graywacke, siltstone, and shale; thickened ranges from 2,000 to 3,000 feet; Parkhead Sandstone - Gray to olive-green sandy shale, conglomeratic sandstone and graywacke; present in Washington County, identification uncertain in west; thickness averages 400 feet; Brallier Fomation - (Woodmont Shale of earlier reports). Medium to dark gray, laminated shale and siltstone; weathers to light olive-gray; grain size coarsens upward; thickness about 2,000 feet in west, about 1,7000 feet in east; and Harrell Shale - Dark gray laminated shale; absent in east where Brallier lies directly on Mahantango, Tully Limestone lies near base in west, in subsurface of Garrett County; total thickness in west 140 to 300 feet.
Chilhowee Group; Harpers Formation (Cambrian)
Harpers Formation - Brown to dark bluish-gray banded shale, to light bluish-gray, finely laminated phyllite; distinctively pale purple in basal part; bedding obscured by cleavage; increasingly metamorphosed toward east from shale to slate and phyllite; estimated thickness 2,000 feet.
Clinton Group, including Rochester Shale (Silurian)
Clinton Group, including Rochester Shale - Gray, thin-bedded calcareous shale and dark gray, thin- to medium-bed7 ded lenticular limestone; thickness 25 to 40 feet; Keefer Sandstone - White to yellowish-gray, thick-bedded protoquartzite and orthoquartzite; calcareous to west; thickness 10 feet in west, increases to 35 feet in east; and Rose Hill Formation - Olive-gray to drab, thin-bedded shale; some purple shale and gray, thin-bedded sandstone; including Cresaptown Iron Sandstone Member - Purple, hematite-cemented, quartzose sandstone; thickness 5 to 30 feet; occurs in lower half of formation; total thickness 300 feet in east, increases to 570 feet in west.
Conemaugh Formation (Pennsylvanian)
Conemaugh Formation - Includes the rocks between the base of the Pittsburgh coal and the top of the Upper Freeport coal; consists of two unnamed members which are separated by the Barton coal; both members are gray and brown claystone, shale, siltstone and sandstone, with several coal beds; lower member also contains redbeds and fossiliferous marine shales; thickness 825 to 925 feet.
Conococheague Limestone (Upper Cambrian to Lower Ordovician )
Conococheague Limestone - Dark blue, laminated, oolitic, argillaceaous, and siliceous limestone, algal limestone, and flat-pebble conglomerate; siliceous shale partings; some sandstone and dolomite; thickness 1,600 to 1,900 feet.
Dunkard Group (Permian)
Dunkard Group - Red and green shale, siltstone, and sandstone, with thin lenticular beds of argillaceous limestone and thin beds of impure coal; thick-bedded, white conglomeratic sandstone at base; thickness greater than 200 feet; occurs only on hilltop
Elbrook Limestone (Cambrian)
Elbrook Limestone - Light blue, laminated, argillaceous limestone and calcareous shale; some dolomite; thickness 1,400 to possibly 3,000 feet.
Frederick Limestone (Cambrian)
Frederick Limestone - Blue, slabby, thin-bedded limestone and minor shale; contains Upper Cambrian (Trempealeauian) faunule; thickness approximately 480 feet.
Gettysburg Shale (Triassic)
Gettysburg Shale - Red shale and soft red sandstone and siltstone; estimated thickness less than 5,000 feet.
Greenbrier Formation (Mississippian)
Greenbrier Formation - Upper part red calcareous shale and sandstone interbedded with greenish-gray and reddish-gray argillaceous limestone; Loyalhanna Limestone Member: Gray to red, cross-bedded, arenaceous calcarenite; total thickness 200 to 300 feet.
Hamilton Group (including Mahantango Formation and Marcellus Shale), and including Tioga Metabentontite Bed, and Needmore Shale (Devonian)
Hamilton Group including Mahantango Formation - Dark gray, laminated shale, siltstone, and very fine-grained sandstone; thickness 600 feet in west, increases to 1,200 feet in east, and Marcellus Shale - Gray-black, thinly laminated, pyritic, carbonaceous shale; thickness 250 feet in east, increases to 500 feet in west. Also includes Tioga Metabentonite Bed - Brownish-gray, thinly laminated shale containing sand-size mica flakes; thickness less than one foot; and Needmore Shale - Olive-gray to black shale and dark, thin-bedded, fossiliferous, argillaceous limestone; thickness ranges from 70 to 145 feet.
Hampshire Formation (Devonian)
Hampshire Formation - Interbedded red shale, red mudstone, and red to brown cross-bedded siltstone and sandstone; some thin green shale; greenish-gray sandstone and shale toward top; fragmentary plant fossils; thickness 1,400 to 2,000 feet in west, increases to 3,800 feet in east.
Helderberg Formation and Keyser Limestone (Devonian)
Helderberg Formation, including Licking Creek Limestone Member - (Becraft Limestone of earlier reports.) Present only in east. Medium gray, medium-grained limestone near top; bedded black chert and thin-bedded limestone in middle; silty argillaceous limestone and shale near base; contains tongues of Shriver and Mandata; thickness 110 feet; Mandata Shale Member - Dark brown to black, thin-bedded shale; fossiliferous; thickness 20 to 30 feet in west, intertongues with Licking Creek Limestone Member in east; Corriganville Limestone Member (Head) - (New Scotland Limestone of earlier reports.) Medium gray, medium-grained, medium-bedded limestone, interbedded with chert; fossiliferous; thickness 15 to 30 feet; New Creek Limestone Member - (Coeymans Limestone of earlier reports.) Medium gray, thick-bedded, coarse-grained limestone; fossiliferous; thickness 9 to 10 feet. Limestone changes facies eastward into sandstone, the Elbow Ridge Sandstone Member - Medium-bedded, medium- to coarse-grained, calcarous sandstone; thickness 10 to 18 feet.; and the Keyser Limestone - Dark gray, thin- to thick-bedded, fine- to coarse-grained calcarenite; contains nodular limestone, dolomitic limestone, and calcarous shale; cherty near top; fossiliferous; thickness 200 to 300 feet.
Juniata Formation (Ordovician)
Juniata Formation - Red to greenish-gray, thin- to thick-bedded siltstone, shale, subgraywacke, and protoquartzite; interbedded conglomerate; thickness 180 feet in east, increases to 500 feet in west.
Martinsburg Formation (Ordovician)
Martinsburg Formation - Upper part rhythmically interbedded graywackes, siltstones, and dark shales; lower part dark brown, dark gray, and black, thin-bedded fissile shale; thickness 2,000 to 2,500 feet.
Mauch Chunk Formation (Mississippian)
Mauch Chunk Formation - Red and green shale, reddish-purple mudstone, and red, green, brown, and gray thin-bedded and cross-bedded sandstones; thickness 500 feet in west, increases to about 800 feet in east.
McKenzie Formation (Silurian)
McKenzie Formation - Gray, thin-bedded shale and argillaceous limestone; interbedded red sandstone and shale in east; thickness 160 feet in western Washington County, increases to 300 feet in east and 380 feet in west.
Monongahela Formation (Pennsylvanian)
Monongahela Formation - Interbedded claystone, argillaceous limestone, shale, sandstone, and coal beds; Waynesburg coal at top; Pittsburg coal at base; thickness 240 feet in west, increases to 375 feet in east.
New Oxford Formation (Triassic)
New Oxford Formation - Red, maroon, and gray sandstone, siltstone, and shale; basal conglomerate member: From vicinity of Maryland Rte. 73 and southward, limestone conglomerate with red and gray calcareous matrix; northward, quartz conglomerate with red sandy matrix; estimated total thickness 4,500 feet.
Oriskany Group including Ridgeley Sandstone and Shriver Chert (Devonian)
Oriskany Group, including Ridgeley Sandstone - White, medium- to coarse-grained, fossiliferous, calcareous orthoquartzite; thickness 160 feet in west. Medium to dark gray cherty, arenaceous limestone in east; thickness 50 feet; and Shriver Chert - Dark gray, brown, and black silty shales, cherty shales, and nodular and bedded black chert; fossiliferous; thickness 170 feet in west, upper boundary gradational with Ridgeley. Thickness 14 feet in east where the lower Shriver intertongues with the Licking Creek Limestone Member of the Helderberg Formation
Pocono Group, including the Purslane Sandstone and Rockwell Formation (Mississippian)
Pocono Group - Gray, white, tan, and brown, thin- to thick-bedded, cross-bedded sandstone, locally conglomeratic; interbedded gray and reddish-brown shale, mudstone, and siltstone; fragmentary plant fossils. Undifferentiated in Garrett and western Allegeny Counties. Includes Purslane Sandstone - White, thick-bedded, coarse-grained sandstone and conglomerate with thin coal beds and red shales. Eastern Allegany and Washington Counties. And also inlcudes Rockwell Formation - Coarse-grained arkosic sandstone, fine-grained conglomerate, and buff shale; dark shale with thin coal beds near base. Eastern Allegany and Washington Counties.
Tomstown Dolomite (Cambrian)
Tomstown Dolomite - Interbedded light gray to yellowish-gray, thin- to thick-bedded dolomite and limestone; some shale layers; gradational contact with Antietam; thickness 200 to 1,000 feet.
Tonoloway Limestone (Silurian)
Tonoloway Limestone - Gray, thin-bedded limestone, dolomitic limestone, and calcareous shale; thin sandstone member in east 20 feet above base; fossiliferous; thickness 400 feet in east, increases to 600 feet in west.
Waynesboro Formation (Cambrian)
Waynesboro Formation - Upper part red, gray, and yellowish-brown, thin-bedded siltstone, shale, and ripple-marked, cross-bedded sandstone; lower part interbedded dark gray to red shale and thin-bedded dolomite; thickness approximately 600 feet.
Wills Creek Shale and Bloomsburg Formation (Silurian)
Wills Creek Shale - Olive to yellowish-gray, thin-bedded mudstone, calcareous shale, argillaceous limestone, and sandstone; thickness 450 feet in west, increases to 600 feet in east; and Bloomsburg Formation - Bright red, hematitic, thin- to thick-bedded sandstone and shale; some dark sandstone and green shale; Cedar Creek Limestone Member - Dark gray, fine- to medium-grained argillaceous limestone, occurs in middle part of formation; total thickness 20 feet in west, increases to 200 feet in east.

Maine

Devonian Chapman Sandstone (Devonian)
Devonian Chapman Sandstone
Ordovician - Cambrian Aziscohos Formation (Ordovician - Cambrian)
Ordovician - Cambrian Aziscohos Formation
Ordovician - Cambrian Saint Daniel formation quartzite and red and green shale (Ordovician - Cambrian)
Ordovician - Cambrian Saint Daniel formation quartzite and red and green shale
Ordovician Munsungun Lake Formation (Ordovician)
Ordovician Munsungun Lake Formation
Ordovician Quimby formation (Ordovician)
Ordovician Quimby formation
Silurian Ames Knob formation (Silurian)
Silurian Ames Knob formation
Silurian Hersey formation (Silurian)
Silurian Hersey formation
Silurian - Ordovician Lobster Lake Formation (Silurian - Ordovician)
Silurian - Ordovician Lobster Lake Formation
Silurian Perry Mountain formation (Silurian)
Silurian Perry Mountain formation
Silurian Rangeley Formation "A""member (Silurian)
Silurian Rangeley Formation "A" member
Silurian Rangeley Formation "B" member (Silurian)
Silurian Rangeley Formation "B" member"
Silurian Rangeley Formation "C" member (Silurian)
Silurian Rangeley Formation "C" member
Silurian Sangerville Formation (Silurian)
Silurian Sangerville Formation
Silurian Sangerville Formation sulfidic pelite member (Silurian)
Silurian Sangerville Formation sulfidic pelite member
Silurian Smalls Falls Formation (Silurian)
Silurian Smalls Falls Formation
Silurian Smalls Falls Formation? (Silurian)
Silurian Smalls Falls Formation?
Silurian Waterville Formation (Silurian)
Silurian Waterville Formation
Silurian Waterville Formation limestone member (Silurian)
Silurian Waterville Formation limestone member

Michigan

Bass Island Dolomite (Late Silurian)
Bass Island Dolomite
Bayport Limestone (Mississippian)
Bayport Limestone
Bedford Shale (Late Devonian)
Bedford Shale
Cataract Formation (Early Silurian)
Cataract Formation
Coldwater Shale (Mississippian)
Coldwater Shale
Ellsworth Shale (Late Devonian)
Ellsworth Shale
Grand River Formation (Pennsylvanian)
Grand River Formation
Jacobsville Sandstone (Middle Proterozoic)
Jacobsville Sandstone - Red, brown, and white quartzose sandstone, and minor siltstone, shale and conglomerate
Michigan Formation (Mississippian)
Michigan Formation
Munising Formation (Late Cambrian)
Munising Formation
Oronto Group; Freda Sandstone (Middle Proterozoic)
Oronto Group; Freda Sandstone - Mainly reddish-brown, medium- to fine-grained lithic arkosic sandstone, siltstone, and micaceous silty shale.
Oronto Group; Nonesuch Shale (Middle Proterozoic)
Oronto Group; Nonesuch Shale - Gray, green, and brown lithic siltstone, shale, and sandstone. Copper sulfides and native copper occur locally near base
Point Aux Chenes Shale (Late Silurian)
Point Aux Chenes Shale
Prairie du Chien Group (Early Ordovician)
Prairie du Chien Group
Queenston Shale (Late Ordovician)
Queenston Shale
Red beds (Jurassic)
Red beds
Saginaw Formation (Pennsylvanian)
Saginaw Formation
Salina Group (Late Silurian)
Salina Group
Stonington Formation (Late Ordovician)
Stonington Formation
Traverse Group (Middle Devonian)
Traverse Group
Trempealeau Formation (Late Cambrian)
Trempealeau Formation
Trenton Limestone (Late Ordovician)
Trenton Limestone

Minnesota

Animikie Group; Shale, siltstone, feldspathic graywacke, and associated volcaniclastic rocks (Early Proterozoic)
Animikie Group; Shale, siltstone, feldspathic graywacke, and associated volcaniclastic rocks - Includes the Rove Formation in Cook County, the Virginia Formation in St. Louis, Itasca, and Lake Counties, and the Thomson Formation in Carlton County
Chicksaw Member of the Little Cedar Formation (Cedar Valley Group) (Devonian)
Chicksaw Member of the Little Cedar Formation (Cedar Valley Group) - Light-gray to medium-gray shale and silty shale
Coleraine Formation (Cretaceous)
Coleraine Formation - Jasper-pebble conglomerate, sandstone, and shale of diverse origin on the Mesabi range of northern Minnesota, and unnamed sandstone and shale of nonmarine to marine origin in east-central Minnesota
Cretaceous rocks, undivided (Cretaceous)
Cretaceous rocks, undivided - Dakota, Graneros, Greenhorn, Carlie, Niobara, and Pierre formations and their nonmarine equivalents in northwestern, southwestern, and southeastern Minnesota
Decorah Shale (Middle Ordovician) (Middle Ordovician)
Decorah Shale (Middle Ordovician) - Light-greenish-gray shale and lesser amounts of coquinoid limestone, especially in the upper half of the formation. Mapped as a separate unit where possible.
Fond du Lac Formation (Middle Proterozoic)
Fond du Lac Formation - Red to dark-brown shale, feldspathic sandstone, and arkose of fluvial origin. Includes the Oldenberg Point Member, a pronounced basal unit of quartz-pebble conglomerate in the Duluth area.
Jurassic rocks, undivided (Jurassic)
Jurassic rocks, undivided - Unnamed units of green, gray, brown, and red shale, white to tan micritic limestone and dolostone, and white, fine- to coarse-grained sandstone and siltstone; unit contains nodules of chert and gypsum
Lithograph City Formation, Coralville Formation and Hinckle and Eagle City Members of the Little Cedar Formation (Cedar Valley Group), undivided (Devonian)
Lithograph City Formation, Coralville Formation and Hinckle and Eagle City Members of the Little Cedar Formation (Cedar Valley Group), undivided - Limestone, dolostone, and lesser amounts of shale
Middle Ordovician rocks, undivided (Middle Ordovician)
Middle Ordovician rocks, undivided - Decorah Shale; limestone of the Platteville Formation; shaly rocks of the Glenwood Formation; and St. Peter Sandstone in the Hollandale embayment of southeastern Minnesota
North Range Group; Mahnomen Formation (Early Proterozoic)
North Range Group; Mahnomen Formation - Claystone, shale, siltstone, and graywacke metamorphosed to the greenschist facies
Pokegama Quartzite (Early Proterozoic)
Pokegama Quartzite - Quartz arenite, siltstone, and shale. Shown only in Crow Wing County.
Solor Church Formation (Middle Proterozoic)
Solor Church Formation - Dark-red to dark-brown shale, siltstone, and lithic sandstone of fluvial origin in Scott and Carver Counties; metamorphosed to zeolite facies
Upper Cambrian, undivided (Late Cambrian)
Upper Cambrian, undivided - Jordan Sandstone; dolomite, glauconite, and silty glauconite rocks of the St. Lawerence and Franconia Formation; Ironton and Galesville Sandstones; sandy and shaly rocks of the Eau Claire Formation; and the Mt. Simon Sandstone.

Missouri

CHEROKEE GROUP- Cabaniss Subgroup, Krebs Subgroup (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Middle Desmonian])
CHEROKEE GROUP - Cabaniss Subgroup - cyclic deposits, shale, sandstone, clay and several workable coal beds. Krebs Subgroup - cyclic deposits, sandstone, siltstone, shale, clay and some workable coal beds
CHESTERIAN SERIES (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late [Chesterian])
CHESTERIAN SERIES - FAYETTEVILLE FORMATION, BATESVILLE FORMATION, HINDVILLE LIMESTONE, VIENNA LIMESTONE, TAR SPRINGS SANDSTONE, GLEN DEAN FORMATION, HARDINSBURG FORMATION, GOLCONDA FORMATION, CYPRESS FORMATION, PAINT CREEK FORMATION, YANKEETOWN SANDSTONE, RENAULT FORMATION, AUX VASES SANDSTONE, STE. GENEVIEVE LIMESTONE
DECORAH GROUP, PLATTIN GROUP (Phanerozoic | Paleozoic | Ordovician-Middle [Mohawkian])
DECORAH GROUP, PLATTIN GROUP
DEVONIAN SYSTEM (Phanerozoic | Paleozoic | Devonian-Early Devonian-Middle(?) Devonian-Late)
DEVONIAN SYSTEM - CHATTANOOGA SHALE, SYLAMORE SANDSTONE, FORTUNE FORMATION, HOLTS SUMMIT SANDSTONE, SNYDER CREEK SHALE, CEDAR VALLEY LIMESTONE, LOUISIANA LIMESTONE, SAVERTON SHALE, GRASSY CREEK SHALE, TURPIN SANDSTONE, BUSHBERG SANDSTONE, GLEN PARK LIMESTONE, St. LARENT LIMESTONE, BEAUVAIS SANDSTONE, GRAND TOWER LIMESTONE, CLEAR CREEK CHERT, LITTLE SALINE LIMESTONE, GRASSY KNOB CHERT, BAILEY FORMATION
DOUGLAS GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Upper Virgilian])
DOUGLAS GROUP - cyclic deposits, dominantly shale with sandstone, and limestone.
ELVINS GROUP- (INCLUDING DERBY-DOERUN DOLOMITE, DAVIS FORMATION), BONNETERRE DOLOMITE (Phanerozoic | Paleozoic | Cambrian-Furongian [Croixian])
ELVINS GROUP - (INCLUDING DERBY - DOERUN DOLOMITE - alternating thin dolomite, siltstone, and shale; DAVIS FORMATION - glauconitic shale with fine - grained sandstone, limestone, and dolomite); BONNETERRE DOLOMITE - dolomite, dolomitic limestone, and limestone; glauconitic in lower part
JOACHIM DOLOMITE, DUTCHTOWN FORMATION (Phanerozoic | Paleozoic | Ordovician-Middle [Mohawkian])
JOACHIM DOLOMITE, DUTCHTOWN FORMATION
KANSAS CITY GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Upper Missourian])
KANSAS CITY GROUP - cyclic deposits, limestone and shale with minor sandstone and coal.
KINDERHOOKIAN SERIES (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early [Kinderhookian])
KINDERHOOKIAN SERIES - NORTHVIEW SHALE, SEDALIA FORMATION, COMPTON LIMESTONE, BACHELOR FORMATION CHOUTEAU GROUP, HANNIBAL SHALE, HORTON CREEK LIMESTONE
LANSING GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Upper Missourian])
LANSING GROUP - cyclic deposits of limestone and shale
LEEMON FORMATION, MAQUOKETA GROUP, CAPE LIMESTONE, KIMMSWICK LIMESTONE, NOIX-CYRENE LIMESTONE, MAQUOKETA SHALE (Phanerozoic | Paleozoic | Ordovician-Middle Ordovician-Late)
LEEMON FORMATION, MAQUOKETA GROUP INCLUDING: (GIRARDEAU LIMESTONE, ORCHARD CREEK SHALE, THEBES SANDSTONE, CAPE La CROIX SHALE), CAPE LIMESTONE, KIMMSWICK LIMESTONE, NOIX - CYRENE LIMESTONE, MAQUOKETA SHALE
MARMATON GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Middle Desmonian])
MARMATON GROUP - cyclic deposits, shale and limestone with sandstone, clay and several coal beds, some workable
OSAGEAN SERIES (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early [Osagean])
OSAGEAN SERIES - KEOKUK LIMESTONE, BURLINGTON LIMESTONE, ELSEY FORMATION, REEDS SPRING FORMATION, PIERSON LIMESTONE, FERN GLEN FORMATION
PENNSYLVANIAN UNDIFFERENTIATED (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
PENNSYLVANIAN UNDIFFERENTIATED
PLEASANTON GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Upper Missourian])
PLEASANTON GROUP - dominantly shale and sandstone with minor coal.
RIVERTON FORMATION, BURGNER FORMATION (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atokan])
RIVERTON FORMATION - shale, clay, coal. BURGNER FORMATION - limestone
SHAWNEE GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Upper Virgilian])
SHAWNEE GROUP - cyclic deposits, limestone and shale with sandstone and siltstone.
SILURIAN SYSTEM (Phanerozoic | Paleozoic | Silurian-Early Silurian-Middle(?) Silurian-Late)
SILURIAN SYSTEM - JOLIET LIMESTONE, BOWLING GREEN DOLOMITE, BRYANT KNOB FORMATION, BAINBRIDGE FORMATION, SEXTON CREEK LIMESTONE
SMITHVILLE DOLOMITE, POWELL DOLOMITE, COTTER DOLOMITE, JEFFERSON CITY DOLOMITE (Phanerozoic | Paleozoic | Ordovician-Early [Ibexian])
SMITHVILLE DOLOMITE, POWELL DOLOMITE, COTTER DOLOMITE, JEFFERSON CITY DOLOMITE - fine crystalline, silty, cherty dolomite, and oolitic chert with local sandstone beds
UNDIFFERENTIATED (Phanerozoic | Paleozoic | Ordovician)
UNDIFFERENTIATED (ORDOVICIAN ROCKS)
WABAUNSEE GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Upper Virgilian])
WABAUNSEE GROUP - cyclic deposits, principally shale, sitlstone, sandstone with thin limestone beds and minor coal

Mississippi

Montana

Basal part of Cody shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Basal part of Cody shale: gray and dark-gray shale with some sandstone beds; in north end of Big Horn Basin includes the Telegraph Creek formation.
Bearpaw shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Bearpaw shale: Dark-gray and brownish clay shale; thick units of nonfissile bentonitic shale; calcareous and ferruginous concretions throughout; contains some thick bentonite beds.
Belle Fourche shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Belle Fourche shale: dark blue-gray siliceous shale with many calcareous and ferruginous concretions and intercalated thin layers of bentonite.
Carlile shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Carlile shale: dark-gray shale with calcareous and ferruginous concretions; middle part commonly sandy
Claggett formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Claggett formation: chiefly dark-gray shale with iron-stained concretions; locally sandstone present; numerous bentonite beds near base.
Fort Union formation (Phanerozoic | Cenozoic | Tertiary Cretaceous-Late | Paleocene)
Fort Union formation: Clay shale, siltstone, and sandstone; local lenses of impure limestone, and numerous lignitic beds; contains Tertiary plant and animal fossils but no dinosaurs; base generally placed at the lowest of the succession of lignite beds within it; includes the Tongue River member, Lebo shale member, and Tullock member.
Horsethief sandstone (Phanerozoic | Mesozoic | Cretaceous-Late)
Horsethief sandstone: shaly sandstone grading upward into massive brownish cliff-forming sandstone with local concentrations of magnetite in beds near top.
Niobrara formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Niobrara formation: chiefly calcareous shale with limestone concretions; many thin bentonite beds locally.
Permian, undifferentiated (Phanerozoic | Paleozoic | Permian)
Permian, undifferentiated: chert, sandstone, limestone, quartzite, and shale with rock phosphate mostly at base; mainly Phosphoria formation
Permian, undifferentiated (Phanerozoic | Paleozoic | Permian)
Permian, undifferentiated: chert, sandstone, limestone, quartzite, and shale with rock phosphate mostly at base; mainly Phosphoria formation
Pierre shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Pierre shale: dark-gray clay shale with calcareous and ferruginous concretions and sandy members.
Wasatch formation (Phanerozoic | Cenozoic | Tertiary)
Wasatch formation: Light-colored massive sandstone; drab-colored shale and coal in southeastern Montana; and variegated, dominantly red beds of clay and sandstone in north-central Montana.

North Carolina

North Dakota

Nebraska

Admire Group (Phanerozoic | Paleozoic | Permian)
Shale and interbedded limestone. Shale is dark gray to light gray, brown, red, or green, sandy, calcareous, and fossiliferous. Interbedded dark- to light-gray, very thin to medium bedded, argillaceous, very fossiliferous limestone beds. Near top of unit a fine-grained, micaceous sandstone bed underlies a stromatolite limestone bed which has distinctive lobate bedding. Approx. max thickness 150 ft
Carlile Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Shale, limestone, and sandstone. At top, locally 5 feet of gray to pale-yellowish brown siltstone or very fine grained sandstone. Upper 200 feet of shale is drak gray to medium gray; locally contains ironstone concretions, and interbedded with thin siltstone. Lower 80 feet of shale is medium gray, calcareous, and contains many very thin bedded, fossiliferous, shaly limestone and calcareous shale layers. Approx. max thickness 300 ft.
Chase Group (Phanerozoic | Paleozoic | Permian)
Limestone and shale. Limestone is light gray to dark gray, yellowish gray to pale yellowish brown. Two limestones in the upper part are thin bedded to medium bedded, argillaceous, cherty and fossiliferous; two limestones in the lower part are medium to massive bedded, very cherty, and fossiliferous. Shale is gray, green, red, redish brown, calcareous, arenaceous, fossiliferous; locally fissile. Approx. max thickness 300 ft.
Council Grove Group (Phanerozoic | Paleozoic | Permian)
Shale and interbedded limestone. Shale is gray, green, red, reddish brown, or maroon, sandy, calcareous, fossiliferous, locally fissile; several fissile black shale beds are in lower 75 feet. Interbedded dark- to light-gray, medium- to thick-bedded, argillaceous, cherty limestone beds are very fossiliferous and locally contain shale partings. Approx. max thickness 300 ft
Dakota Group (Phanerozoic | Mesozoic | Cretaceous-Early)
Upper part is white, light-gray, brownish-gray, yellow, redish-brown, and red sandstone and shale. Sandstone is very fine to coarse grained, friable, micaeous, crossbedded, and lenticular; locally contains gravel near base. contains numerous zones of ironstone and siltstone concretions of variable thickness. Middle part is light-gray, yellow, red brown and dark-gray, sandy carbonaceous shale; commonly contains a zone of concretions near top. Lower part is sandstone similar to that in upper except there are zones of siderite concretions and, locally a basal zone of chert pebbles. Approx. max thickness 600 ft.
Douglas Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgilian])
Shale and limestone. Shale is dark gray to medium gray, red , black, fossiliferous, calcareous and locally sandy. Limestone is dark gray to light gray, thin bedded to thick bedded, fossiliferous and locally sandy. Approx. max thickness 100 ft
Fox Hills Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Consists of fossiliferous, gray, ferruginous and yellowish fine-grained sandstone, arenaceous clays and a few interbeds of gray to brown sandy shale and coal totaling 172 ft thick at that section. Estimated thickness 500 ft.
Greenhorn Limestone and Graneros Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Greenhorn Limestone- medium- to light-gray limestone interbedded with argillaceous limestone, marl and calcareous shale; contains Inoceramus fossils. Upper and lower contacts gradational. Approx. max thickness 30 ft. Graneros Shale- medium- to dark-gray, partly calcareous shale. Interbeds of siltstone, sandstone, and carbonaceous shale, and thin bentonite layers in upper part. Approx. max thickness 60 ft.
Kansas City Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missourian])
Limestone and shale. Limestone is dark gray to light gray, brownish gray, very thin bedded to massive, argillaceous, fossiliferous; contains very thin layers of chert, pyrite crystals, and small flakes of mica near base. Shale is dark gray to light gray, greenish gray, red, and black; locally slighty sandy, calcareous, carbonaeous, fissile, and fossiliferous. Approx. max thickness 200 ft
Lansing Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missourian])
Limestone and shale. Limestone is dark gray to light gray, very thin bedded to massive, sandy fossiliferous, and cherty. Shale is dark gray to light gray, maroon, black, fossiliferous, and calcareous. Approx. max thickness 75 ft
Marmaton Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Desmoinesian])
Shale and limestone. Shale is dark gray to light gray, greenish gray, black, red, silty, sandy carbonaceous, fissile, calcareous; contains scattered limestone nodules. Limestone is medium gray to light gray, red, mottled thin bedded to thick bedded, sandy, shaly, vuggy, fossiliferous. Approx. max thickness 125 ft
Niobrara Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Argillaceous chalk, limestone and shale. Chalk is medium gray to white, interbedded with thin layers of chalky shale; contains many fossil clams, oysters, and formanifera. Limestone is light gray to medium gray and yellowish gray, interbedded with medium-gray chalky shale; also contains fossil clams, oysters, and formanifera. Bedding plans commonly marked by thin layers of gypsum and locally a thin bed of red flint occurs at top of unit. Approx. max thickness 570 ft.
Pierre Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Mostly medium to dark-gray, brownish-gray, and black, fissle clay shale. Locally grades to thin beds of calcareous, silty shale or claystone, marl, shaly sandstone, and sandy shale. Locally contains thin seams of gypsum and sparse selenite crystals. Approx. max thickness 1970 ft.
Shawnee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgilian])
Limestone, shale and siltstone. Limestone is dark gray to very light gray, yellowish gray, very thin bedded to massive bedded, and fossiliferous; locally the thin bedds are argillaceous other beds are oolitic and a few contain chert. Shale is medium gray, greenish gray, pale red, dark redish brown, black, sandy fossiliferous and calcareous; black shale in part is fissile. Siltstone is light gray to greenish yellow, massive, calcareous; locally sandy. Approx. max thickness 200 ft
Wabaunsee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgilian])
Shale, sandstone, and interbedded limestone. Shale is light gray to dark gray, greenish gray, red, or black; contains very thin layers of siltstone; locally very fossiliferous, carbonaceous. Sandstone is brownish gray to yellowish gray, or gray, argillaceous , and micaceous. Limestone is dark gray to medium gray, yellowish gray, thin bedded to thick bedded; very fossiliferous. Contains coal beds less than 1 ft. thick. Approx. max thickness 300 ft

New Jersey

Allentown Dolomite (Lower Ordovician and Upper Cambrian)
Allentown Dolomite (Wherry, 1909) - Very thin to very thick bedded dolomite containing minor orthoquartzite and shale. Upper part is medium-light- to medium-dark-gray, fine- to medium-grained, locally coarse-grained, medium- to very thick bedded dolomite. Floating quartz sand grains and two sequences of medium-light- to very light gray, thin-bedded quartzite and discontinuous, dark-gray chert lenses occur directly below upper contact. Rhythmically bedded lower dolomite beds alternate between light and dark gray weathering, medium and very light gray, fine and medium grained, and thin and medium bedded, which are interbedded with shaly dolomite. Ripple marks, crossbeds, edgewise conglomerate, mud cracks, oolites, and algal stromatolites occur throughout unit, but more typically in lower part. Shaly dolomite increases downward toward lower conformable contact with the Leithsville Formation. Oldest beds contain trilobite fauna of early Late Cambrian age; younger beds contain latest Cambrian fauna (Howell, 1945; Howell and others, 1950). Thickness about 580 m (1,900 ft).
Allentown Dolomite (Lower Ordovician and Upper Cambrian) (Wherry, 1909) (Lower Ordovician and Upper Cambrian)
Allentown Dolomite (Lowest Lower Ordovician and Upper Cambrian) (Wherry, 1909) - Medium- to very light gray, fine- to medium-grained, very thin to very thick bedded dolomite containing minor orthoquartzite and shale. Oolites and algal stromatolites occur throughout unit. Shaly dolomite increases downward towards lower conformable contact with the Leithsville Formation. Unit does not crop out but is known from subsurface borings near Flanders (Volkert and others, 1990). Thickness ranges from 0 to 73 m (0-240 ft) due to erosion.
Bellvale Sandstone (Middle Devonian)
Bellvale Sandstone (Bellvale Flags of Darton, 1894; Willard, 1937) - Upper beds are grayish-red to grayish-purple sandstone containing quartz pebbles as large as 3 cm (1.2 in) in diameter. Lower beds are light-olive-gray- to yellowish-gray- and greenish-black-weathering, medium-gray to medium-bluish-gray very thin to very thick bedded siltstone and sandstone cross-bedded, graded and interbedded with black to dark-gray shale that is locally fossiliferous. More sandstone in upper beds becomes finer downward. Lower contact conformable and placed where beds thicken and volume of shale and siltstone are about equal. The unit is 535 to 610 m (1,750-2,000 ft) thick.
Berkshire Valley and Poxono Island Formations, undivided (Upper Silurian)
Berkshire Valley and Poxono Island Formations, undivided - Thickness ranges from 76 m (250 ft) at Greenwood Lake to 122 m (400 ft) in Longwood Valley. Berkshire Valley Formation (Barnett, 1970) - Commonly yellowish-gray weathering, medium-gray to pinkish-gray, very thin to thin-bedded fossiliferous limestone interbedded with gray to greenish-gray calcareous siltstone and silty dolomite, medium-gray to light-gray dolomite conglomerate, and grayish-black, thinly laminated shale. Lower contact conformable. Thickness ranges from 27 to 38 m (90-125 ft) thick. Poxono Island Formation, (White, 1882; Barnett, 1970) - Very thin to medium-bedded sequence of medium-gray, greenish-gray, or yellowish-gray, mud-cracked dolomite; light-green, pitted, medium-grained calcareous sandstone, siltstone, and edgewise conglomerate containing gray dolomite; and quartz-pebble conglomerate containing angular to subangular pebbles as much as 2 cm (0.8 in.) long. Interbedded grayish-green shales at lower contact are transitional into underlying Longwood Shale. Thickness ranges from 49 to 84 m (160-275 ft) thick.
Boonton Formation (Lower Jurassic)
Boonton Formation (Olsen, 1980) - Reddish-brown to brownish-purple, fine-grained sandstone, siltstone, and mudstone; sandstone commonly micaceous, interbedded with siltstone and mudstone in fining-upward sequences mostly 1.5 to 4 m (5-13 ft) thick. Red, gray and brownish-purple siltstone and black, blocky, partly dolomitic siltstone and shale common in lower part. Irregular mudcracks, symmetrical ripple marks, and burrows, as well as gypsum, glauberite, and halite pseudomorphs are abundant in red mudstone and siltstone. Gray, fine-grained sandstone may have carbonized plant remains and reptile footprints in middle and upper parts of unit. Near Morristown, beds of quartz-pebble conglomerate (unit Jbcq) as much as 0.5 m (1.6 ft) thick interfinger with beds of sandstone, siltstone, and shale. Northeast of Boonton, beds of quartz-pebble conglomerate (not mapped separately as Jbcq) occur locally with conglomerate containing abundant clasts of gneiss and granite in matrix of reddish-brown sandstone and siltstone. Maximum thickness is about 500 m (1,640 ft).
Bushkill Member (Middle Ordovician)
Bushkill Member (Drake and Epstein, 1967) - Interbedded medium- to dark gray, thinly laminated to thick-bedded shale and slate and less abundant medium-gray to brownish-gray, laminated to thin-bedded siltstone. To the southwest, fine-grained, thin dolomite lenses occur near base. Complete turbidite sequences (Bouma, 1962) occur locally, but basal cutout sequences (Tbcde, Tcde or Tde) dominate. Conformable lower contact is placed at top of highest shaly limestone; elsewhere, lower contact is commonly strain slipped. Correlates with graptolite Climacograptus bicornis to Corynoides americanus zones of Riva (1969, 1974) (Parris and Cruikshank, 1992). Thickness ranges from 1,250 m (4,100 ft) in Delaware River Valley to 457 m (1,500 ft) at New York State line.
Cornwall Shale (Middle Devonian)
Cornwall Shale (Hartnagel, 1907) - Black to dark-gray, very-thin- to thickbedded, fissile shale, fossiliferous, interbedded with medium-gray and light-olive-gray to yellowish-gray, laminated to very-thin-bedded siltstone, that increases in upper part of unit. Lower contact probably conformable. About 290 m (950 ft) thick.
Green Pond Conglomerate (Lower (?) and Middle Silurian)
Green Pond Conglomerate (Rogers, 1836) - Medium- to coarse-grained quartz-pebble conglomerate, quartzitic arkose and orthoquartzite, and thin- to thick-bedded reddish-brown siltstone. Grades downward into gray, very dark-red, or grayish-purple, medium- to coarse-grained, thin- to very thick bedded pebble to cobble conglomerate containing clasts of red shale, siltstone, and chert; yellowish-gray sandstone and chert; dark-gray shale and chert; and white-gray and pink milky quartz. Quartz cobbles are as long as 10 cm (4 in.), and rare red shale clasts as much as 46 cm (18 in.) across. Milky quartz pebbles average 2.5 cm (1 in.) in length. Red arkosic quartz-pebble conglomerate and quartzite are more abundant than gray and grayish-green quartzite. Unconformably overlies Martinsburg Formation, Allentown Dolomite, Leithsville Formation, or Proterozoic rocks. About 305 m (1000 ft) thick.
High Point Member (Upper Ordovician)
High Point Member (Drake, 1991) - Medium-dark-gray, thin-bedded shale, siltstone and fine-grained sandstone, containing turbidite sequences Tbcde to Tcde of Bouma (1962). Interbedded with less abundant, light-yellowish-gray-weathering, medium-gray to medium-dark-gray, medium-grained, medium- to thick-bedded and massive, quartz- and calcareous-cemented quartz sandstone containing rip-ups of medium- to dark-gray shale and siltstone that commonly consist of Bouma (1962) turbidite sequences Tab to Ta. Restricted to northeast section of Martinsburg outcrop belt. Thermally metamorphosed near intrusive bodies. Grades along strike to the southwest into Ramseyburg Member by decrease in average grain size, absence of shale rip-ups, and lack of siliceous cement. Lower contact gradational and placed at base of lowermost thick-bedded graywacke or amalgamated graywacke containing shale rip-ups. Unit assigned to Orthograptus ruedemanni zone to Climacograptus spiniferus zone of Riva (1969, 1974) using graptolites collected by Parris and Cruikshank (1992). Thickness ranges from 0 to 1,370 m (0-4,500 ft).
Jacksonburg Limestone and Sequence at Wantage, undivided (Middle Ordovician)
Jacksonburg Limestone and Sequence at Wantage, undivided - Jacksonburg Limestone - Upper part is medium- to dark-gray, laminated to thin-bedded shaly limestone and less abundant medium-gray arenaceous limestone containing quartz-sand lenses. Upper part thin to absent to northeast. Lower part is interbedded medium- to dark-gray, fine- to medium-grained, very thin to medium-bedded fossiliferous limestone and minor medium- to thick-bedded dolomite-cobble conglomerate having a limestone matrix. Unconformable on Beekmantown Group and conformable on the discontinuous sequence at Wantage in the Paulins Kill area. Contains conodonts of North American midcontinent province from Phragmodus undatus to Aphelognathus shatzeri zones of Sweet and Bergstrom (1986). Thickness ranges from 41 to 244m (135-800 ft). Sequence at Wantage - Restricted, discontinuous sequence of interbedded limestone, dolomite, conglomerate, siltstone, and shale. Upper part is medium-yellowish-brown- to olive-gray-weathering, medium- to dark-gray, very fine to fine-grained, laminated to massive limestone and dolomite that grade down into underlying clastic rocks of lower part. Upper part locally absent. Lower part ranges from grayish-red, medium-gray, pale-brown, and greenish-gray to pale-green mudstone and siltstone containing disseminated subangular to subrounded chert-gravel, quartz-sand lenses, and chert-pebble conglomerate. Lower contact unconformable. Thickness ranges from 0 to 46 m (0-150 ft).
Jutland Klippe Sequence, undifferentiated (Middle Ordovician to Upper Cambrian?)
Jutland Klippe Sequence, undifferentiated - Rocks of the Jutland klippe sequence occur in six isolated fragments of the Jutland klippe east of Jutland and two fragments of the Peapack klippe along the Peapack-Ralston fault in the New Jersey Highlands hinterland. The sequence is largely varicolored shale and sandstone, but contains lesser amounts of limestone, dolomite and pebble conglomerate. Lash and Drake (1984) correlate this sequence with the accretionary prism deposits of the Greenwich slice of the Hamburg klippe in eastern Pennsylvania. Rocks of the Jutland klippe sequence were folded and thrust over rocks of the Kittatinny Valley sequence during the Taconic orogeny and then were deformed during the Alleghanian orogeny and again during Mesozoic rifting of eastern North America.
Jutland Klippe Sequence Unit A (lower Middle Ordovician to Upper Cambrian)
Jutland Klippe Sequence Unit A of Perissoratis and others (1979) - Interbedded red, green, and tan shale, sandstone, and dark-gray, aphanitic to fine-grained limestone, which contains floating quartz-sand grains. Grades downward through interbedded sequence of red, green and brown shale to medium-gray to brown, fine- to coarse-grained sandstone and quartz-pebble conglomerate. Lower beds are dark-gray shale and siltstone containing minor dark-gray, aphanitic to fine-grained, medium-bedded limestone. Lower contact is a fault. Contains graptolites in the span of Anisograptus to Isograptus caduceus of Berry (1968) (Perissoratis and others, 1979) and conodonts of the Cordylodus proavus to Paroistodus proteus faunas of the North Atlantic Realm. Thickness is unknown.
Jutland Klippe Sequence Unit B (Middle Ordovician)
Jutland Klippe Sequence Unit B of Perissoratis and others (1979) - Heterogeneous sequence of interbedded red, green, tan and gray shale; interlaminated dolomite and shale; interbedded fine-grained graywacke siltstone and beds or lenses of sandstone; light-gray to pale-pinkish-gray quartzite; and interbedded fine-grained, thin-bedded limestone and red and green shale. Limestone locally resembles an intraformational conglomerate because it is disrupted, boudinaged, and surrounded by shale beds. Lower contact gradational and within interbedded sequence of thin- to medium-bedded sandstone, siltstone, and limestone. Perissoratis and others (1979) placed this contact at boundary between graptolite faunas Isograptus caduceus and Paraglossograptus etheridgei of Berry (1968). The youngest graptolites occur within Climacograptus bicornis zone of Berry (1968). Some shale beds contain conodonts (Ethington and others, 1958; Karklins and Repetski, 1989) and brachiopod fragments. Carbonate and pelitic rocks locally contain conodonts of Prioniodus triangularis to Pygodus anserinus faunas of North Atlantic Realm. Thickness varies due to structural complexity, but may be about 460 to 550 m (1,500-1,800 ft).
Leithsville Formation (Middle and Lower Cambrian)
Leithsville Formation (Wherry, 1909) - Thin- to thick-bedded dolomite containing subordinate siliciclastic rocks. Upper part is medium- to medium-dark-gray, fine- to medium-grained, pitted, friable, mottled and massive dolomite. Middle part is medium-gray, stylolitic, fine-grained, thin- to medium-bedded dolomite that is interbedded with shaly dolomite and, less commonly, vari-colored quartz sandstone, siltstone, and shale. Lower part is medium-gray, medium-grained, medium-bedded dolomite containing quartz-sand grains in stringers and lenses near the contact with the Hardyston Quartzite. Archaeocyathids of Early Cambrian age suggest an intraformational disconformity separating rocks of Middle and Early Cambrian age (Palmer and Rozanov, 1976). Thickness approximately 305 m (1,000 ft).
Leithsville Formation (Middle and Lower Cambrian)
Leithsville Formation (Middle and Lower Cambrian) (Wherry, 1909) - Light- to dark-gray and lightolive-gray, fine- to medium-grained, thin- to medium-bedded dolomite. Grades downward through medium-gray, grayish-yellow, or pinkish-gray dolomite and dolomitic sandstone, siltstone and shale to medium-gray, medium-grained, medium-bedded dolomite containing quartz sand grains as stringers and lenses near the base. Lower contact gradational. Thickness ranges from 0 to 56 m (0-185 ft) due to erosion.
Longwood Shale (Middle (?) and Upper Silurian)
Longwood Shale (Darton, 1894) - Dark-reddish-brown, thin- to very thick bedded shale interbedded with cross-bedded, very dark red, very thin to thin-bedded sandstone and siltstone. Lower contact conformable. About 100 m (330 ft) thick.
Marcellus Shale (Middle Devonian)
Marcellus Shale (Vanuxem, 1840) - Medium-gray weathering, dark-gray to grayish-black, thin- to thick-bedded, fossiliferous, fissile and limonite-stained locally arenaceous shale. Lower contact grades downward over 12 m (40 ft) from black shale through limy shale, into silty limestone of the Buttermilk Falls Limestone (documented in drill core data of Fletcher and Woodrow, 1970). Approximately 274 m (900 ft) thick.
Martinsburg Formation (Upper and Middle Ordovician) (Upper and Middle Ordovician)
Martinsburg Formation (Middle and Upper Ordovician) - Yellowish-gray weathering, light-olive- to dark-gray, phyllonitic shale containing thin, discontinuous silty lenses. Crops out in two locations along the Reservoir fault north of Bowling Green Mountain (Barnett, 1976; Herman and Mitchell, 1991). Contact relations and thickness unknown.
Minisink Limestone and New Scotland Formation, undivided (Lower Devonian)
Minisink Limestone and New Scotland Formation, undivided - Minisink Limestone (Epstein and others, 1967) - Light-medium-gray-weathering, medium-gray, fine-grained, medium-bedded, partly massive, argillaceous fossiliferous limestone. Some nodules and lenses of purer limestone occur locally. Lower contact gradational. Thickness uniformly 7 m (23 ft). New Scotland Formation (Clarke and Schuchert, 1899) - Upper part is dark-gray, very fine grained, laminated to thin-bedded siliceous shale containing pods of medium-dark-gray, very fine grained limestone; scattered thin beds and lenses of medium-gray, fine-grained argillaceous fossiliferous limestone; and small dark-gray chert nodules. Lower part is medium-dark-gray, thin-bedded, siliceous, fossiliferous calcareous shale. Contains thin beds and lenses of medium-gray, fine-grained, highly fossiliferous, argillaceous limestone containing nodules, lenses and, locally, irregular beds of dark-gray chert. Lower contact abrupt and placed at top of calcareous quartz sandstone. Total thickness is approximately 23 m (75 ft).
Oriskany Group, undivided (Lower Devonian)
Oriskany Group, undivided (Willard, 1938) - Thickness ranges from 38 m (125 ft) in southwest to 52 m (170 ft) in northeast. Ridgely Sandstone (Swartz and others, 1913) - White-weathering, medium-gray, medium- to thick-bedded, carbonate-cemented quartz-pebble conglomerate and coarse quartz sandstone, which contain abundant brachiopods. Moderately well sorted, subrounded sand gains. Unit thins northeastward and pinches out at Peters Valley. Lower contact abrupt. Thickness ranges from 0 to 10 m (0-32 ft). Shriver Chert (Swartz and others, 1913) - Medium- to dark-gray-weathering, black to dark-gray, medium-to-thick-bedded siltstone and shale containing interbedded black chert and local chert-bearing limestone. Present only in southwestern part of outcrop area where lower contact is gradational with silty limestone of Glenarie Formation. Thickness ranges from 0 to 9 m (0-30 ft). Glenarie Formation (Chadwick, 1908) - Medium-gray-weathering, medium- to dark-gray, fine-grained, thin- to medium-bedded, fossiliferous, silty limestone, and local chert lenses. Unit thickens to northeast. Lower contact probably gradational. Thickness ranges from 17 to 52 m (55-170 ft).
Passaic Formation (Lower Jurassic and Upper Triassic)
Passaic Formation - Predominantly red beds consisting of argillaceous siltstone; silty mudstone; argillaceous, very fine grained sandstone; and shale; mostly reddish-brown to brownish-purple, and grayish-red. Red beds occur typically in 3- to 7-m (10- to 23-ft-)-thick, cyclic playa-lake-mudflat sequences and fining-upward fluvial sequences. Lamination is commonly indistinct due to burrowing, desiccation, and paleosol formation. Where layering is preserved, most bedforms are wavy parallel lamination and trough and climbing-ripple cross lamination. Calcite- or dolomite-filled vugs and flattened cavities, mostly 0.5 to 0.2 mm (0.02-0.08 in) across, occur mostly in the lower half. Sand-filled burrows, 2 to 5 mm (0.08-0.2 in) in diameter, are prevalent in the upper two-thirds of the unit. Desiccation cracks, intraformational breccias, and curled silt laminae are abundant in the lower half. Lake cycles, mostly 2 to 5 m (7-16 ft) thick, have a basal, greenish-gray, argillaceous siltstone; a medial, dark-gray to black, pyritic, carbonaceous, fossiliferous, and, in places, calcareous lake-bottom fissile mudstone or siltstone; and an upper thick-bedded, gray to reddish and purplish-gray argillaceous siltstone with desiccation cracks, intraformational breccias, burrows, and mineralized vugs. Thickness of the formation between Sourland Mountain and Sand Brook syncline is about 3,500 m (11,483 ft).
Passaic Formation (Lower Jurassic and Upper Triassic)
Passaic Formation (Olsen, 1980) - Reddish-brown to brownish-purple and grayish-red siltstone and shale (JTrp) maximum thickness 3,600 m (11,810 ft). At places contains mapped sandy mudstone (JTrpms), sandstone (JTrps), conglomeratic sandstone (JTrpsc) and conglomerate containing clasts of quartzite (JTrpcq), or limestone (JTrpcl). Formation coarsens up section and to the southwest. Quartzite conglomerate unit (JTrpcq) is reddish-brown pebble conglomerate, pebbly sandstone, and sandstone, in upward-fining sequences 1 to 2 m (3-6 ft) thick. Clasts are subangular to subrounded, quartz and quartzite in sandstone matrix. Sandstone is medium to coarse grained, feldspathic (up to 20 percent feldspar), and locally contains pebble and cobble layers. Conglomerate thickness exceeds 850 m (2,790 ft). Limestone conglomerate unit (JTrpcl) is medium-bedded to massive, pebble to boulder conglomerate. Clasts are subangular dolomitic limestone in matrix of brownish- to purplish-red sandstone to mudstone; matrix weathers light-gray to white near faults. Maximum thickness unknown. Conglomeratic sandstone (JTrpsc) is brownish-red pebble conglomerate, medium- to coarse-grained, feldspathic sandstone and micaceous siltstone; unit is planar to low-angle trough cross laminated, burrowed, and contains local pebble layers. Unit forms upward-fining sequences 0.5 to 2.5 m (1.6-8 ft) thick. Conglomeratic sandstone thickness exceeds 800 m (2,625 ft). Sandstone (JTrps) is interbedded grayish-red to brownish-red, medium- to fine-grained, medium- to thick-bedded sandstone and brownish-to purplish-red coarse-grained siltstone; unit is planar to ripple cross-laminated, fissile, locally calcareous, containing desiccation cracks and root casts. Upward-fining cycles are 1.8 to 4.6 m (6-15 ft) thick. Sandstone beds are coarser and thicker near conglomerate units (JTrpcq, JTrpcl). Maximum thickness about 1,100 m (3,610 ft). Sandy mudstone (JTrpms) is reddish-brown to brownish-red, massive, silty to sandy mudstone and siltstone, which are bioturbated, ripple cross-laminated and interbedded with lenticular sandstone. To southwest where similar lithologic units also occur, they have not been mapped separately, but have been included in undivided unit JTrp. Rhythmic cycles 2 to 7 m (7-23 ft) of thick gray-bed sequences (Trpg), termed Van Houten cycles by Olsen (1985), contain basal thin-bedded to finely laminated shale to siltstone, which grade upward through laminated to microlaminated, locally calcareous mudstone to siltstone and finally into massive silty mudstone. Lowest part of cycle has some desiccation features and local fossils; middle part has highest organic content and the most fossils; highest part contains mudcracks, burrows, and root casts. Gray-bed cycles are abundant in lower half of Passaic Formation and less common in upper half. Rocks of the Passaic Formation have been locally thermally metamorphosed to hornfels where in contact with the Orange Mountain Basalt, diabase dikes, and sheetlike intrusions. Total thickness of formation ranges from 3500 to 3600 m (11480-11810 ft).
Passaic Formation gray bed (Lower Jurassic and Upper Triassic)
Passaic Formation gray bed - Upper Triassic gray lake deposits (Trpg) consist of gray to black silty mudstone, gray and greenish- to purplish-gray argillaceous siltstone, black shale, and medium- to dark-gray, argillaceous, fine-grained sandstone and are abundant in the lower half of the Passaic Formation. Gray lakebeds occur in groups of two to five cycles although they also occur as single cycles in some parts of the formation. Several lakebed sequences consisting of one or two thick groups of drab-colored beds as much as 30 m (98 ft) thick or more can be traced over tens of kilometers. Many gray-bed sequences are locally correlated within fault blocks; some can be correlated across major faults or intrusive rock units. Thickness of the (entire Passaic) formation between Sourland Mountain and Sand Brook syncline is about 3,500 m (11,483 ft).
Passaic Formation gray bed (Lower Jurassic and Upper Triassic)
Passaic Formation gray bed - Rhythmic cycles 2 to 7 m (7-23 ft) of thick gray-bed sequences (Trpg), termed Van Houten cycles by Olsen (1985), contain basal thin-bedded to finely laminated shale to siltstone, which grade upward through laminated to micro-laminated, locally calcareous mudstone to siltstone and finally into massive silty mudstone. Lowest part of cycle has some desiccation features and local fossils; middle part has highest organic content and the most fossils; highest part contains mudcracks, burrows, and root casts. Gray-bed cycles are abundant in lower half of Passaic Formation and less common in upper half.
Port Ewen Shale (Lower Devonian)
Port Ewen Shale (Clarke, 1903) - Upper part is medium-gray- weathering, dark-to- medium-dark-gray, thin- to medium-bedded, fossiliferous, calcareous siltstone and shale. Lower part is medium-dark-gray, irregularly bedded nonfossiliferous, calcareous silty shale. Lower contact abrupt and placed at top of uppermost medium-gray, argillaceous limestone in Minisink Limestone. Thickness approximately 46 m (150 ft).
Ramseyburg Member (Upper and Middle Ordovician)
Ramseyburg Member (Drake and Epstein, 1967) - Interbedded medium- to dark-gray, to brownish-gray, fine- to medium-grained, thin- to thick-bedded graywacke sandstone and siltstone and medium- to dark-gray, laminated to thin-bedded shale and slate. Unit may form complete turbidite sequences, Tabcde (Bouma, 1962), but basal cutout sequences Tcde dominate. Basal scour, sole marks, and soft-sediment distortion of beds are common in graywacke. Thermally metamorphosed near intrusive bodies. Lower contact placed at bottom of lowest thick- to very thick bedded graywacke, but contact locally grades through sequence of dominantly thin-bedded shale and slate and minor thin- to medium-bedded discontinuous and lenticular graywacke beds in the Bushkill member. Parris and Cruikshank (1992) correlate unit with Orthograptus ruedemanni to lowest part of Climacograptus spiniferus zones of Riva (1969, 1974). Thickness ranges from 640 m (2,100 ft) in Delaware River Valley, to 1,524 m (5,000 ft) near Stillwater, to 1067 m (3,500 ft) at New York State line.
Shawangunk Formation (Middle and Lower Silurian)
Shawangunk Formation (Mather, 1840; Epstein and Epstein, 1972) - Upper part is medium- to medium-dark-gray, or dark-greenish-gray, medium- to thick-bedded sandstone and pebble conglomerate having well rounded grains, some of which are limonite stained. Conglomerate consists of matrix-supported quartz and subordinate shale pebbles as long as 5 cm (2 in.) in poorly to well-sorted, planar tabular to trough crossbedded sandstone. Local black to dark-greenish-gray, thin-bedded shale near upper contact. Middle part, occurring in southwest and sporadically in northeast, is light- to medium-dark-gray, greenish-gray, interbedded thin- to medium-bedded, planar tabular to trough cross-bedded shale and sandstone. Grains are well rounded and moderately to well sorted. Contains sparse graphite flakes. Lower part is light- to medium-gray to light-olive-gray, thin- to thick-bedded quartz and feldspathic sandstone, quartzite, and quartz-pebble conglomerate, which is matrix-supported, poorly to well sorted, cross to planar bedded. Clasts are primarily quartz and sparse dark-gray argillite and black chert. Sandstone is feldspathic and locally approaches an arkose in compostion. Lower contact unconformable and, at places, is a fault of small displacement. Thickness approximately 427 m (1,400 ft).
Skunnemunk Conglomerate (Middle Devonian)
Skunnemunk Conglomerate (Darton, 1894) - Grayish-purple to grayish-red, thin- to very thick bedded, locally cross-bedded, polymictic conglomerate and sandstone containing clasts of white vein quartz, red and green quartzite and sandstone, red and gray chert, and red shale; interbedded with medium-gray, thin-bedded sandstone and greenish-gray and grayish-red, mud-cracked shale. Conglomerate and sandstone matrix is primarily hematite and microcrystalline quartz. Conglomerate cobbles range to 16.5 cm (6.5 in) long, and average cobble size increases in upper part of unit. Lower contact conformable and gradational as defined by Kummel and Weller (1902). About 915 m (3,000 ft) thick.
Stockton Formation (Upper Triassic)
Stockton Formation - Predominantly medium- to coarse-grained, light-gray, light-grayish-brown, or yellowish- to pinkish-gray arkosic sandstone and medium- to fine-grained, violet-gray to reddish-brown arkosic sandstone; with lesser, reddish to purplish-brown, silty mudstone, argillaceous siltstone, and shale. Some coarse-grained sandstone in lower part contains thick beds of conglomerate (Trsc) which have been mapped in the vicinity of Stockton. Sandstone, deposited in high-gradient stream channels, is mostly planar bedded with scoured bases containing pebble lags and mudstone rip-up clasts. Upper part of channel beds are burrowed. Large-scale trough crossbeds occur in some very coarse grained sandstone beds; smaller scale trough and climbing-ripple cross lamination occur in the upper part of channel sequences and in finer grained sandstone beds. Typical floodplain mudstones are irregularly thin bedded and extensively burrowed. Floodplain beds are thicker and more numerous in the central Newark basin, near the Delaware River. Thickness of the unit (including Trsc) near Stockton is about 1,240 m (4,068 ft).
Stockton Formation (Upper Triassic)
Stockton Formation (Kummel, 1897) - Light-gray, light-grayishbrown, yellowish- to pinkish-gray, or violet-gray to reddish-brown, medium- to coarse-grained arkosic sandstone and reddish- to purplish-brown mudstone, silty mudstone, argillaceous siltstone, and shale. Mudstone, siltstone and shale beds thicker and more numerous in central Newark basin west of Round Valley Reservoir. Sandstones mostly planar-bedded, with scoured bases containing pebble lags and mudstone rip-ups. Unit is coarser near Newark basin border fault, where poorly exposed, reddish-brown to pinkish-white, medium- to coarse-grained, feldspathic pebbly sandstone and conglomerate (Trss) and pebble to cobble quartzite conglomerate (Trscq). Maximum thickness of formation about 1,240 m (4,070 ft).
Wantage Sequence (Middle Ordovician)
Wantage Sequence (Monteverde and Herman, 1989) - Restricted, discontinuous sequence of interbedded limestone, dolomite, conglomerate, siltstone, and shale. Upper part is medium-yellowish-brown- to olive-gray-weathering, medium- to dark-gray, very fine to fine-grained, laminated to massive limestone and dolomite that grade down into underlying clastic rocks of lower part. Upper part locally absent. Lower part ranges from grayish-red, medium-gray, pale-brown, and greenish-gray to pale-green mudstone and siltstone containing disseminated subangular to subrounded chert-gravel, quartz-sand lenses, and chert-pebble conglomerate. Lower contact unconformable. Thickness ranges from 0 to 46 m (0-150 ft).

New Mexico

Abo Formation (Phanerozoic | Paleozoic | Permian)
Abo Formation; red beds, arkosic at base, finer and more mature above; Wolfcampian; may include limestone beds of Pennsylvanian age (Virgilian) in Zuni Mountains. In Robledo Mountains the Abo may be considered a member of the Hueco Formation
Abo Formation, lower part (Phanerozoic | Paleozoic | Permian)
Lower part of Abo Formation; Wolfcampian, and in part Virgilian ?
Abo Formation, upper part (Phanerozoic | Paleozoic | Permian)
Upper part of Abo Formation; Wolfcampian
Bell Canyon Formation (Phanerozoic | Paleozoic | Permian)
Bell Canyon Formation; basin facies-sandstone, limestone, and shale; Guadalupian
Bursum Formation (Phanerozoic | Paleozoic | Permian)
Bursum Formation; shale, arkose, and limestone; earliest Permian
Carlile Shale (Phanerozoic | Mesozoic | Cretaceous)
Carlile Shale; limited to northeastern area; Turonian-Coniacian
Cherry Canyon Formation (Phanerozoic | Paleozoic | Permian)
Cherry Canyon Formation; basin facies-sandstone, limestone, and shale
Cliff House Sandstone (Phanerozoic | Mesozoic | Cretaceous)
Cliff House Sandstone; transgressive marine sandstone; Campanian
Cutoff Shale (Phanerozoic | Paleozoic | Permian)
Cutoff Shale; in Brokeoff Mountains only
Dakota Sandstone and Rio Salado Tongue of the Mancos Shale (Phanerozoic | Mesozoic | Cretaceous)
Dakota Sandstone and Rio Salado Tongue of the Mancos Shale. In northwest Socorro County locally includes overlying Tres Hermanos Formation
Fort Hayes Limestone Member of Niobrara Formation (Phanerozoic | Mesozoic | Cretaceous)
Fort Hays Limestone Member of Niobrara Formation
Gallup Sandstone and underlying D-Cross Tongue of Mancos Shale (Phanerozoic | Mesozoic | Cretaceous)
Gallup Sandstone and underlying D-Cross Tongue of the Mancos Shale; Turonian
Graneros Shale (Phanerozoic | Mesozoic | Cretaceous)
Graneros Shale; limited to northeastern area; Cenomanian
Graneros Shale and Greenhorn Formation (Phanerozoic | Mesozoic | Cretaceous)
Graneros Shale and Greenhorn Formation; limited to northeastern area; lower Turonian and Cenomanian
Grayburg and Queen Fromations (Phanerozoic | Paleozoic | Permian)
Grayburg and Queen Formations; sandstone, gypsum, anhydrite, dolomite, and red mudstone; Guadalupian
Greenhorn Formation (Phanerozoic | Mesozoic | Cretaceous)
Greenhorn Formation; limited to northeastern area. The Upper member (Bridge Creek Limestone) can be traced into western area where it is commonly shown as a bed-rank unit in Mancos Shale on detailed maps
Greenhorn Formation and Carlile Shale (Phanerozoic | Mesozoic | Cretaceous)
Greenhorn Formation and Carlile Shale, undivided; locally includes Graneros Shale
Hueco Formation (Phanerozoic | Paleozoic | Permian)
Hueco Formation; limestone unit restricted to south-central area; Pendejo Tongue divides Abo Formation into upper and lower parts; Wolfcampian
La Ventana Tongue (Phanerozoic | Mesozoic | Cretaceous)
La Ventana Tongue of the Cliff House Sandstone
Lead Camp Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Lead Camp Formation; San Andres and Organ Mountains
Lewis Shale (Phanerozoic | Mesozoic | Cretaceous)
Lewis Shale; marine shale and mudstone
Mancos Formation and Beartooth Quartzite (Phanerozoic | Mesozoic | Cretaceous)
Mancos Formation and Beartooth Quartzite (and Sarten Sandstone); Mancos includes what was formerly referred to as Colorado Shale which in turn may include equivalents of Tres Hermanos Formation
Mancos Shale (Phanerozoic | Mesozoic | Cretaceous)
Mancos Shale; divided into Upper and Lower parts by Gallup Sandstone
Mancos Shale, lower part (Phanerozoic | Mesozoic | Cretaceous)
Mancos Shale, Lower part
Mancos Shale, upper part (Phanerozoic | Mesozoic | Cretaceous)
Mancos Shale, Upper part
McRae Formation (Phanerozoic | Mesozoic | Cretaceous)
McRae Formation; Engle basin - Cutter sag area; Maastrichtian
Moreno Hill Formation and Atarque Sandstone (Phanerozoic | Mesozoic | Cretaceous)
Moreno Hill Formation and Atarque Sandstone; in Salt Lake coal field and extreme southern Zuni basin; Turonian
Mulatto Tongue of Mancos Shale (Phanerozoic | Mesozoic | Cretaceous)
Mulatto Tongue of Mancos Shale
Nacimiento Formation (Phanerozoic | Cenozoic | Tertiary)
Nacimiento Formation; Paleocene, San Juan Basin
Ojo Alamo Formation (Phanerozoic | Cenozoic | Tertiary)
Ojo Alamo Formation; Paleocene, San Juan Basin
Percha Shale (Phanerozoic | Paleozoic | Devonian)
Percha Shale; southern Caballo Mountains; includes the Onate and Sly Gap Formations
Pescado Tongue of the Mancos Shale and Gallup Sandstone (Phanerozoic | Mesozoic | Cretaceous)
Pescado Tongue of the Mancos Shale and Gallup Sandstone; in Zuni Basin only. Pescado is chrono-stratigraphic equivalent of Juana Lopez Member of Mancos Shale; Turonian
Pierre Shale and Niobrara Formation (Phanerozoic | Mesozoic | Cretaceous)
Pierre Shale and Niobrara Formation
Rio Salado Tongue of Mancos Shale (Phanerozoic | Mesozoic | Cretaceous)
Rio Salado Tongue of the Mancos Shale. Overlies Twowells Tongue of Dakota Sandstone; mapped only where Tres Hermanos Formation or the Atarque Sandstone is present; mapped as Kdr in parts of Socorro County; Turonian
Sandia Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
Sandia Formation; predominately clastic unit (commonly arkosic) with minor black shales, and limestone in lower part; locally includes Osha Canyon Formation in Nacimiento Mountains
Satan Tongue of Mancos Shale (Phanerozoic | Mesozoic | Cretaceous)
Satan Tongue of Mancos Shale
Vermejo Formation and Trinidad Sandstone (Phanerozoic | Mesozoic | Cretaceous)
Vermejo Formation and Trinidad Sandstone; Maastrichtian
Zuni Sandstone (Phanerozoic | Mesozoic | Jurassic)
Zuni Sandstone; consists of undivided equivalents of the Summerville Formation and Bluff Sandstone; restricted to Zuni Basin area

Nevada

Antler Sequence of Silberling and Roberts (1962) (Pennsylvanian to Late Permian )
ANTLER SEQUENCE OF SILBERLING AND ROBERTS (1962) (Middle Pennsylvanian to Early or Late Permian) (Guadalupian)-Conglomerate, sandy to conglomeratic limestone, limestone, sandstone, and calcareous shale. Thin detrital and carbonate sequence within main part of Antler orogenic belt. Includes units such as Sunflower Formation of Bushnell (1967) in Elko County, Battle Formation, Antler Peak Limestone, and Edna Mountain Formation in Lander and western Eureka Counties, and Wildcat Peak Formation in northern Nye County
Argillaceous limestone, chert, and shale (Devonian)
ARGILLACEOUS LIMESTONE, CHERT, AND SHALE-Elko and Eureka Counties
Chert, shale, argillite, siltstone, quartzite, and greenstone (Cambrian to Devonian)
CHERT, SHALE, ARGILLITE, SILTSTONE, QUARTZITE, AND GREENSTONE-Undivided siliceous assemblage. Mostly Ordovician
Cherty limestone and sparse dolomite, shale, and sandstone (Permian)
CHERTY LIMESTONE AND SPARSE DOLOMITE, SHALE, AND SANDSTONE (Lower and Upper Permian)-Includes units such as Park City Group and equivalent rocks in northern Nevada and Toroweap Formation and Kaibab Limestone in southern Nevada
Conglomerate, sandstone, shale, and dolomite of Diablo Formation below and shale, sandstone, and conglomerate of Candelaria Formation above (Early Permian to Early Triassic)
CONGLOMERATE, SANDSTONE, SHALE, AND DOLOMITE OF DIABLO FORMATION BELOW AND SHALE, SANDSTONE, AND CONGLOMERATE OF CANDELARIA FORMATION ABOVE (Lower or Upper Permian to Lower Triassic)-Mineral, Esmeralda, and northwestern Nye Counties
Dolomite and limestone (Middle Cambrian to Ordovician)
DOLOMITE AND LIMESTONE-Undivided Cambrian and Ordovician rocks in part of Clark County; mostly Cambrian.
Dolomite, limestone, and minor amounts of sandstone and quartzite (Devonian)
DOLOMITE, LIMESTONE, AND MINOR AMOUNTS OF SANDSTONE AND QUARTZITE-Includes units such as Sevy and Simonson Dolomites, Guilmette and Nevada Formations, and Devils Gate Limestone.
Dunlap Formation (Early Jurassic to Middle Jurassic)
DUNLAP FORMATION (Lower and Middle Jurassic)-Conglomerate, sandstone, greenstone, felsite, and tuff. Locally contemporaneous with folding and thrusting. Mineral County and adjacent parts of Esmeralda and Nye Counties
Elder Sandstone (Silurian)
ELDER SANDSTONE-Feldspathic sandstone, siltstone, shale, and chert. Lander County.
Harmony Formation (Late Cambrian)
HARMONY FORMATION (Upper Cambrian)-Feldspathic and arkosic sandstone and minor amounts of shale, limestone, and chert.
Havallah sequence of Silberling and Roberts (1962) (Mississippian to Permian)
HAVALLAH SEQUENCE OF SILBERLING AND ROBERTS (1962)-Chert, argillite, shale, greenstone, and minor amounts of siltstone, sandstone, conglomerate, and limestone. Includes Schoonover Formation of Fagan (1962) and Reservation Hill Formation in Elko County, Farrel Canyon Formation in southwestern Humboldt County, Havallah and Pumpernickel Formations in Pershing, Lander, and parts of Humboldt Counties, and rocks originally considered a part of the Pablo and Excelsior Formations in northern Nye, northern Esmeralda, and southern Mineral Counties. Assignment of some rocks to the Havallah sequence in the East Range, Pershing County, is highly uncertain. Includes rocks ranging in age from Late Mississippian to Early Permian
Limestone and dolomite, locally thick sequences of shale and siltstone (Late Cambrian to Middle Cambrian)
LIMESTONE AND DOLOMITE, LOCALLY THICK SEQUENCES OF SHALE AND SILTSTONE-Includes units such as Pioche Shale, Eldorado Dolomite, Geddes Limestone, Secret Canyon Shale, Hamburg Dolomite, Dunderberg Shale, and Windfall Formation of northern Nevada and Carrara, Bonanza King, and Nopah Formations of southern Nevada.
Limestone and minor amounts of dolomite and shale (Mississippian)
LIMESTONE AND MINOR AMOUNTS OF DOLOMITE AND SHALE-Includes units such as Rogers Spring and Monte Cristo Limestones
Limestone and sparse dolomite, siltstone, and sandstone (Mississippian to Early Permian)
LIMESTONE AND SPARSE DOLOMITE, SILTSTONE, AND SANDSTONE-Includes units such as undivided Riepe Spring Limestone of Steele (1960) and Ely Limestone or their equivalent in Elko, White Pine, and northern Lincoln Counties and most of the Bird Spring Formation and Callville Limestone in Clark and southern Lincoln Counties. Includes some stratigraphically higher Permian rocks in Leppy Peak, easternmost Elko County.
Limestone, dolomite, and shale (Mississippian to Permian)
LIMESTONE, DOLOMITE, AND SHALE (Upper Paleozoic)-Includes Van Duzer Limestone of Decker (1962)
Limestone, dolomite, shale, and quartzite (Ordovician)
LIMESTONE, DOLOMITE, SHALE, AND QUARTZITE-Includes units such as Pogonip Group, Eureka Quartzite, and Ely Springs Dolomite. Where Ely Springs Dolomite or equivalent rocks are included in SOc unit, this unit includes only the Pogonip Group and Eureka Quartzite or their equivalents.
Limestone, minor amounts of dolomite, shale, and sandstone; locally thick conglomerate units (Triassic)
LIMESTONE, MINOR AMOUNTS OF DOLOMITE, SHALE, AND SANDSTONE; LOCALLY THICK CONGLOMERATE UNITS (Lower, Middle, and Upper Triassic)-Includes Tobin, Dixie Valley, Favret, Augusta Mountain, and Cane Spring Formations and Star Peak Group in central Nevada and Grantsville and Luning Formations in west-central Nevada
Moenkopi Formation, Thaynes Formation, and related rocks (Early Triassic to Middle Triassic)
MOENKOPI FORMATION, THAYNES FORMATION, AND RELATED ROCKS (Lower Triassic)-Marine deposits of siltstone, limestone, and sparse conglomerate
Phyllite, shale, and limestone (Middle Cambrian to Ordovician)
PHYLLITE, SHALE, AND LIMESTONE-Locally includes chert and quartzite. Includes Tennessee Mountain Formation of Bushnell (1967) in western Elko County, Broad Canyon sequence of Means (1962) in Lander County, and rocks originally mapped as Palmetto Formation in Toiyabe and Toquima Ranges, northern Nye County
Platy limestone and limy siltstone, chert at base (Silurian to Early Devonian)
PLATY LIMESTONE AND LIMY SILTSTONE, CHERT AT BASE-Includes units such as Roberts Mountains Formation, and Storff Formation and Chellis Limestone of Decker (1962). Locally includes rocks of Early Devonian age at top.
Quartzite and minor amounts of conglomerate, phyllitic siltstone, limestone, and dolomite (Late Proterozoic to Early Cambrian)
QUARTZITE AND MINOR AMOUNTS OF CONGLOMERATE, PHYLLITIC SILTSTONE, LIMESTONE, AND DOLOMITE-Includes Prospect Mountain Quartzite, Osgood Mountain Quartzite, and Gold Hill Formation in northern Nevada, and Stirling Quartzite, Wood Canyon Formation, and Zabriskie Quartzite in southern Nevada.
Quartzite, phyllitic siltstone, conglomerate, limestone, and dolomite (Late Proterozoic)
QUARTZITE, PHYLLITIC SILTSTONE, CONGLOMERATE, LIMESTONE, AND DOLOMITE-Includes McCoy Creek Group (excluding Stella Lake Quartzite) in east-central Nevada and Johnnie Formation in southern Nevada.
Sandstone and quartzite (Cambrian)
SANDSTONE AND QUARTZITE-Includes Tapeats Sandstone and related rocks. Rests on Precambrian metamorphic rocks.
Scott Canyon Formation (Early Cambrian to Middle Cambrian)
SCOTT CANYON FORMATION (Lower or Middle Cambrian)-Chert, shale, greenstone, and sparse limestone and quartzite. Southeast Humboldt County and northwest Lander County.
Sedimentary rocks (Late Cretaceous to Oligocene)
SEDIMENTARY ROCKS-Includes Sheep Pass Formation (Eocene) and related units and unnamed tuffaceous sedimentary rocks
Shale and chert (Silurian)
SHALE AND CHERT-Includes Fourmile Canyon Formation in Eureka County and Noh Formation of Riva (1970) and unnamed rocks in Elko County.
Shale and thin-bedded or laminated limestone; also thinly interbedded limestone and chert (Middle Cambrian to Late Cambrian)
SHALE AND THIN-BEDDED OR LAMINATED LIMESTONE; ALSO THINLY INTERBEDDED LIMESTONE AND CHERT-Includes units such as Preble and Emigrant Formations
Shale, chert, and limestone (Ordovician)
SHALE, CHERT, AND LIMESTONE-Includes Aura Formation of Decker (1962) in northwest Elko County and Perkins Canyon Formation of Kay and Crawford (1964) in northern Nye County
Shale, chert, and minor amounts of quartzite, greenstone, and limestone (Ordovician)
SHALE, CHERT, AND MINOR AMOUNTS OF QUARTZITE, GREENSTONE, AND LIMESTONE-Includes units such as Vinini Formation of north-central Nevada, Palmetto Formation in southern and central parts of Esmeralda County, and Comus Formation in Humboldt County. Locally includes rocks of Silurian and Devonian age.
Shale, mudstone, siltstone, sandstone, and carbonate rock; sparse volcanic rock (Late Triassic to Early Jurassic)
SHALE, MUDSTONE, SILTSTONE, SANDSTONE, AND CARBONATE ROCK; SPARSE VOLCANIC ROCK (Upper Triassic and Lower Jurassic)-Includes Auld Lang Syne Group, Nightingale sequence of Bonham (1969), and Gabbs and Sunrise Formations
Shale, sandstone, volcanogenic clastic rocks, andesite, rhyolite, and locally thick carbonate units (Late Triassic to Early Cretaceous)
SHALE, SANDSTONE, VOLCANOGENIC CLASTIC ROCKS, ANDESITE, RHYOLITE, AND LOCALLY THICK CARBONATE UNITS-Undivided sequence locally containing recognizable equivalents of the Luning and Dunlap Formations
Shale, siliceous siltstone, chert, and minor amounts of limestone (Devonian)
SHALE, SILICEOUS SILTSTONE, CHERT, AND MINOR AMOUNTS OF LIMESTONE-Includes Cockalorum Wash Formation of northern Nye County and Woodruff Formation and unnamed rocks in Elko County
Shale, siltstone, sandstone, chert-pebble conglomerate, and limestone (Devonian to Mississippian)
SHALE, SILTSTONE, SANDSTONE, CHERT-PEBBLE CONGLOMERATE, AND LIMESTONE-Includes units such as Pilot Shale, Joana Limestone, Chainman Shale, and Diamond Peak Formation in northern and eastern Nevada and Narrow Canyon Limestone, Mercury Limestone, and Eleana Formation in southern Nevada
Siliceous and volcanic rocks (Ordovician to Devonian)
SILICEOUS AND VOLCANIC ROCKS-Chert, shale, quartzite, greenstone, and minor amounts of limestone. Includes units such as Valmy Formation of north-central Nevada and some rocks mapped as Palmetto Formation in northern part of Esmeralda County and adjacent parts of Mineral and Nye Counties. Locally includes rocks of Silurian and Devonian age.
Siliceous and volcanic rocks (Mississippian)
SILICEOUS AND VOLCANIC ROCKS-In Humboldt County, consists of altered pillow lavas, coarse volcanic breccias, clastic limestone, and minor amounts of sandstone, shale, siliceous shale, and chert of the Goughs Canyon Formation (Lower and Upper Mississippian). In the East Range, Pershing County, consists of quartzite, conglomerate, slate, limestone, chert, and greenstone of the Inskip Formation (Mississippian?).
Siltstone, sandstone, limestone, and dolomite (commonly silty or sandy) and gypsum (Early Permian)
SILTSTONE, SANDSTONE, LIMESTONE, AND DOLOMITE (COMMONLY SILTY OR SANDY), AND GYPSUM (Lower Permian)-Includes units such as Rib Hill Sandstone and Pequop Formation of Steele (1959) in Elko County, Rib Hill Sandstone and Arcturus Formation in White Pine County, Queantoweap Sandstone of NcNair (1951), Hermit Shale, and Coconino Sandstone in Clark and southern Lincoln Counties.
Silty limestone, minor amounts of shale, and some greenstone (Permian to Early Triassic)
SILTY LIMESTONE, MINOR AMOUNTS OF SHALE, AND SOME GREENSTONE-Unnamed sequence in Adobe Range, northern Elko County
Slaven Chert (Devonian)
SLAVEN CHERT-Chert and sparse limy sandstone, siltstone, and limestone. Lander County
Volcanic flows and flow breccias, chiefly of andesitic composition, tuffs, sparse sandstone and graywacke (Permian to Jurassic)
VOLCANIC FLOWS AND FLOW BRECCIAS, CHIEFLY OF ANDESITIC COMPOSITION, TUFFS, SPARSE SANDSTONE AND GRAYWACKE-Includes Happy Creek Volcanic Series and related rocks in Humboldt County and similar rocks in Washoe and Pershing Counties; includes andesite breccias and volcanogenic sedimentary rocks in Mineral County

New York

Akron Dolostone (Upper Silurian)
Akron Dolostone - Bertie Formation-dolostone, shale.
Akron Dolostone (Upper Silurian)
Akron Dolostone - Bertie Formation-dolostone, shale.
Angola and Rhinestreet Shales (Upper Devonian)
Angola and Rhinestreet Shales.
Austin Glen Formation (Middle Ordovician)
Austin Glen Formation - graywacke, shale
Austin Glen Formation (Middle Ordovician)
Austin Glen Formation - graywacke, shale
Austin Glen Formation (Pawlet in Vermont) (Middle Ordovician)
Austin Glen Formation (Pawlet in Vermont) - graywacke, shale.
Beers Hill, Dunn Hill, Millport, and Moreland Shales (Upper Devonian)
Beers Hill, Dunn Hill, Millport, and Moreland Shales.
Beers Hill, Dunn Hill, Millport, and Moreland Shales; Grimes Siltstone (Upper Devonian)
Beers Hill, Dunn Hill, Millport, and Moreland Shales; Grimes Siltstone.
Black River Group (Middle Ordovician)
Black River Group - In Black River Valley: Chaumont Limestone-locally cherty; Lowville Limestone; Pamelia Formation-dolostone, shale, arkose. In Champlain Valley: Amsterdam, Isle La Motte, and Lowville Limestones: Pamelia Dolostone.
Bloomsburg Formation (Upper Silurian)
Bloomsburg Formation - shale, sandstone; Guymard Quartzite; Otisville Shale; Shawangunk Conglomerate-sandstone, conglomerate.
Briarcliff Dolostone and Pine Plains Formation (Cambrian)
Briarcliff Dolostone and Pine Plains Formation - Columbia County: Pine Plains-dolostone, oolite, shale.
Briarcliff Dolostone and Pine Plains Formation (Cambrian)
Briarcliff Dolostone and Pine Plains Formation - Briarcliff -l ocally cherty; Pines Plains - dolostone, shale, oolite.
Camillus and Syracuse Formations (Upper Silurian)
Camillus and Syracuse Formations - shale, dolostone, gypsum, salt.
Camillus, Syracuse, and Vernon Formations (Upper Silurian)
Camillus, Syracuse, and Vernon Formations - shale, dolostone, salt, and gypsum.
Cashaqua and Middlesex Shales (Upper Devonian)
Cashaqua and Middlesex Shales.
Clinton Group (Lower Silurian)
Decew Dolostone, Rochester Shale, Irondequoit and Merriton Limestones.
Clinton Group (Silurian)
Clinton Group - Herkimer Sandstone including Joslin Hill and Jordanville Members; Kirkland Hematite; Willowvale Shale; Westmoreland Hematite; Sauquoit Formation-sandstone, shale; Otsquago Sandstone; Oneida Conglomerate.
Clinton Group (Lower Silurian)
Clinton Group - Herkimer Sandstone; Kirkland Hematite; Willowvale Shale; Westmoreland Hematite; Sauquoit Formation-sandstone, shale; Oneida Conglomerate.
Cobleskill Limestone (Upper Silurian)
Cobleskill Limestone - Bertie and Camillus Formations-dolostone, shale.
Cobleskill Limestone (Upper Silurian)
Cobleskill Limestone; Bertie, Camillus, and Syracuse Formations - shale, dolostone; Brayman Shale.
Conneaut Group, undivided (Upper Devonian)
Conneaut Group, undivided - In west: Ellicott and Dexterville Formations-shale, siltstone. In east: Germania Formation-shale, sandstone; Whitesville Formation-shale, sandstone; Hinsdale Sandstone; Wellsville Formation-shale, sandstone; Cuba Sandstone.
Conneaut Group, undivided (Upper Devonian)
Conneaut Group, undivided - Germania Formation-shale, sandstone; Whitesville Formation-shale, sandstone; Hinsdale Sandstone; Wellsville Formation-shale, sandstone; Cuba Sandstone.
Connoquenessing and Sharon Formations (Lower Pennsylvanian)
Connoquenessing and Sharon Formations - sandstone, shale; Sharon Formation-shale, sandstone, conglomerate; Olean Conglomerate 50-100 ft. (15-30 m).
Cuyahoga and Knapp Formations (Lower Mississippian)
Cuyahoga and Knapp Formations - Cuyahoga Formation-shale, sandstone; Corry Sandstone; Knapp Formation-shale, conglomerate 60-100 ft. (20-30 m).
Decew Dolostone and Rochester Shale (Lower Silurian)
Decew Dolostone and Rochester Shale
Decew Dolostone and Rochester Shale (Lower Silurian)
Decew Dolostone and Rochester Shale
Elizaville Formation (Cambrian - Ordovician)
Elizaville Formation - shale, argillite, quartzite.
Elizaville Formation (Cambrian - Ordovician)
Elizaville Formation - shale, argillite, quartzite.
"Enfield" and Kattel Formations (Upper Devonian)
"Enfield" and Kattel Formations - shale, siltstone, sandstone.
Frankfort Formation (Upper Ordovician)
Frankfort Formation - shale, siltstone.
Gardeau Formation (Upper Devonian)
Gardeau Formation - shale, siltstone; Roricks Glen Shale.
Genesee Group (Upper Devonian)
Genesee Group - West River Shale; Genundewa Limestone; Penn Yan and Geneseo Shales; North Evans Limestone.
Genesee Group (Upper Devonian)
Genesee Group - West River Shale; Genundewa Limestone; Penn Yan and Geneseo Shales; all except Geneseo replaced eastwardly by Ithaca Formation-shale, siltstone and Sherburne Siltstone.
Germantown Formation (Cambrian)
Germantown Formation - south of Troy; shale, conglomerate, limestone.
Germantown Formation (Cambrian)
Germantown Formation - shale, limestone, conglomerate.
Glenerie Formation (Lower Devonian)
Glenerie Formation - limestone, chert.
Glenerie Formation (Lower Devonian)
Glenerie Formation - limestone, chert; Port Jervis Formation (near Port Jervis only)-shale, limestone, chert.
Gowanda, South Wales, and Dunkirk Shales (Upper Devonian)
Gowanda, South Wales, and Dunkirk Shales.
Honesdale Formation (Upper Devonian)
Honesdale Formation - sandstone, shale.
Honesdale Formation (Upper Devonian)
Honesdale Formation - sandstone, shale.
Iberville Shale (in Vermont) (Middle Ordovician)
Iberville Shale (in Vermont)
Irondequoit Limestone thru Kodak Sandstone (Lower Silurian)
Irondequoit Limestone thru Kodak Sandstone - includes: Irondequoit Limestone, Rockway Dolostone, Hickory Corners Limestone, Neahga Shale, and Kodak Sandstone.
Irondequoit Limestone thru Kodak Sandstone (Lower Silurian)
Irondequoit Limestone thru Kodak Sandstone - includes: Irondequoit Limestone, Williamson Shale; Wolcott Furnace Hematite; Wolcott Limestone; Sodus Shale; Bear Creek Shale; Wallington Limestone; Furnaceville Hematite; Maplewood Shale; Kodak Sandstone.
Lower Beers Hill Shale (Upper Devonian)
Lower Beers Hill Shale - Dunn Hill, Millport, and Moreland Shales.
Lower Beers Hill Shale (Upper Devonian)
Lower Beers Hill Shale - Dunn Hill, Millport, and Moreland Shales.
Lower Walton Formation (Upper Devonian)
Lower Walton Formation - shale, sandstone, conglomerate.
Lower Walton Formation (Upper Devonian)
Lower Walton Formation - shale, sandstone, conglomerate.
Ludlowville Formation (Middle Devonian)
Ludlowville Formation - In west: Deep Run Shale, Tichenor Limestone, Wanakah and Ledyard Shales, Centerfield Limestone Members. In east: King Ferry Shale and other members, Stone Mill Sandstone Member.
Ludlowville Formation (Middle Devonian)
Ludlowville Formation - Deep Run Shale, Tichenor Limestone, Wanakah and Ledyard Shales, Centerfield Limestone Members.
Machias Formation (Upper Devonian)
Machias Formation - shale, siltstone; Rushford Sandstone; Caneadea, Canisteo, and Hume Shales; Canaseraga Sandstone; South Wales and Dunkirk Shales; In Pennsylvania: Towanda Formation-shale, sandstone.
Machias Formation (Upper Devonian)
Machias Formation - shale, siltstone; Rushford Sandstone; Caneadea, Canisteo, and Hume Shales; Canaseraga Sandstone; South Wales and Dunkirk Shales.
Marcellus Formation (Middle Devonian)
Marcellus Formation - Pecksport, Solsville, Otsego, and Chittenango shale and sandstone Members, Cherry Valley Limestone, and Union Springs Shale Members.
Medina Group (Lower Silurian)
Medina Group - consists of: Thorold Sandstone; Grimsby Formation-sandstone, shale; Power Glen and Cabot Head Shales; Whirlpool Sandstone.
Medina Group (Lower Silurian)
Medina Group - Grimsby Formation-sandstone, shale.
Moscow Formation (Middle Devonian)
Moscow Formation - Windom and Kashong Shales, Menteth Limestone Members.
Moscow Formation (Middle Devonian)
Moscow Formation - In west: Windom and Kashong Shales, Menteth Limestone Members; In east: Cooperstown Shale Member, Portland Point Limestone Member.
Moscow Formation (Middle Devonian)
Moscow Formation - in west: Cooperstown and Portland Point shale and sandstone Members; In east: "Manorkill" and Portland Point shale and sandstone Members.
Moscow Formation (Middle Devonian)
Moscow Formation - shale, sandstone.
Mount Merino and Indian River Formations (Ordovician)
Mount Merino and Indian River Formations - shale, argillite, chert.
Mount Merino and Indian River Formations (Ordovician)
Mount Merino and Indian River Formations - shale, slate, cherts.
Mount Merino and Indian River Formations (Ordovician)
Mount Merino and Indian River Formations - shale, slate, cherts.
Nassau Formation (Cambrian ?)
Nassau Formation - shale, quartzite.
Nassau Formation (Cambrian ?)
Nassau Formation - south of 43 degrees; slate, shale, thin quartzite, includes Stuyvesant Conglomerate, Diamond Rock Quartzite, Curtis Mountain Quartzite, and Bomoseen Graywacke Members.
New Milford Formation (Upper Devonian)
New Milford Formation - "New Milford" Formation: sandstone, shale.
Normanskill Formation (Middle Ordovician)
Normanskill Formation - shale, argillite, siltstone.
Normanskill Shale (Middle Ordovician)
Normanskill Shale - minor mudstone, sandstone.
Northeast Shale and Shumla Siltstone (Upper Devonian)
Northeast Shale and Shumla Siltstone.
Nunda Formation (Upper Devonian)
Nunda Formation - sandstone, shale.
Nunda Formation (Upper Devonian)
Nunda Formation - sandstone, shale.
Nunda Formation, West Hill Formation (Upper Devonian)
Nunda Formation, West Hill Formation - Nunda: sandstone, shale; West Hill: shale, siltstone; Corning Shale.
Oneonta Formation (Middle - Upper Devonian)
Oneonta Formation - shale, sandstone.
Oneonta Formation (Middle - Upper Devonian)
Oneonta Formation - shale, sandstone, conglomerate.
Oneonta Formation (Middle - Upper Devonian)
Oneonta Formation - shale, sandstone.
Onondaga Limestone (Lower to Middle Devonian)
Onondaga Limestone - Seneca, Morehouse (cherty), and Nedrow Limestone Members, Edgecliff cherty Limestone Member, local bioherms, Buttermilk Falls Limestone Member; Schoharie Formation-shale, limestone; Carlisle Center Siltstone; Esopus Shale.
Onondaga Limestone (Lower to Middle Devonian)
Onondaga Limestone - Schoharie Formation-shale, limestone; Carlisle Center Siltstone; Esopus Shale.
Oswayo and Venango Formations (Upper Devonian)
Oswayo and Venango Formations - shale, siltstone, sandstone; replaced eastwardly by Cattaraugus Formation-shale, sandstone, conglomerate.
Panther Mountain Formation (Middle Devonian)
Panther Mountain Formation - shale, siltstone, sandstone.
Panther Mountain Formation (Middle Devonian)
Panther Mountain Formation - shale, siltstone, sandstone.
Plattekill and Ashokan Formations (Middle Devonian)
Plattekill Formation - shale, sandstone; Ashokan Formation-shale, sandstone.
Plattekill and Ashokan Formations (Middle Devonian)
Plattekill Formation - shale, sandstone; Ashokan Formation-shale, sandstone.
Poultney Formation ("A" Member) (Cambrian)
Poultney Formation ("A" Member) - north of Troy: shale, limestone; Hatch Hill Formation-shale, dolostone; West Castleton Formation-shale, limestone, conglomerate.
Poultney Formation ("A" Member) (Cambrian)
Poultney Formation ("A" Member) - shale, limestone; Hatch Hill Formation-shale, dolostone; West Castleton Formation-shale, limestone, conglomerate.
Poultney Formation ("B" and "C" Members) (Ordovician)
Poultney Formation ("B" and "C" Members) - shale, slate, siltstone.
Poultney Formation ("B" and "C" Members) (Ordovician)
Poultney Formation ("B" and "C" Members) - north of Troy; shale, slate, siltstone.
Pulaski and Whetstone Gulf Formations (Upper Ordovician)
Pulaski and Whetstone Gulf Formations - shale, siltstone.
Pulaski and Whetstone Gulf Formations (Upper Ordovician)
Pulaski and Whetstone Gulf Formations - siltstone, shale.
Pulaski and Whetstone Gulf Formations (Upper Ordovician)
Pulaski and Whetstone Gulf Formations - siltstone, shale.
Queenston Formation (Upper Ordovician)
Queenston Formation - shale, siltstone.
Queenston Shale (Upper Ordovician)
Queenston Shale
Rensselaer Graywacke (Cambrian? )
Rensselaer Graywacke - minor shale.
Rondout Formation (Upper Silurian)
Rondout Formation - dolostone, limestone; Binnewater Sandstone; High Falls Shale; Warwarsing Limestone; Decker Limestone; Bossardville Limestone; Poxono Island Formation-shale, dolostone.
Schenectady Formation (Upper Ordovician)
Schenectady Formation - graywacke, sandstone, siltstone, shale.
Skaneateles Formation (Middle Devonian)
Skaneateles Formation - In west: Levanna Shale and Stafford Limestone Members; In east: Butternut, Pompey, and Delphi Station Shale Members, Mottville Sandstone Member.
Skaneateles Formation (Middle Devonian)
Skaneateles Formation - Levanna Shale, Stafford Limestone Members.
Slide Mountain Formation (Upper Devonian)
Slide Mountain Formation - sandstone, shale, conglomerate.
Slide Mountain Formation (Upper Devonian)
Slide Mountain Formation - sandstone, shale, conglomerate.
Slide Mountain Formation (Upper Devonian)
Slide Mountain Formation - sandstone, shale, conglomerate.
Sonyea Group (Upper Devonian)
Sonyea Group - In west: Cashaqua and Middlesex Shales. In east: Rye Point Shale; Rock Stream ("Enfield") Siltstone; Pulteney, Sawmill Creek, Johns Creek, and Montour Shales.
Stissing Formation (Cambrian)
Stissing Formation - dolostone, shale.
Stony Point Shale (Middle Ordovician)
Stony Point Shale
Stuyvesant Falls Formation (Ordovician)
Stuyvesant Falls Formation - shale, siltstone.
Stuyvesant Falls Formation (Ordovician)
Stuyvesant Falls Formation - south of Troy; shale, siltstone.
Syracuse Formation (Upper Silurian)
Syracuse Formation - dolostone, shale, gypsum, salt.
Theresa (Galway) Formation (Cambrian)
Theresa (Galway) Formation - dolostone, sandstone, shale.
Trenton Group (Middle Ordovician)
Trenton Group - In Black River Valley: Cobourg Formation-Hillier shale and limestone Member, Hallowell limestone Member; Denley, Sugar River, Kings Falls, and Rockland Limestones. In Champlain Valley: Glens Falls Formation-Montreal shale and limestone Member, Larrabee limestone Member.
Unadilla Formation (Middle - Late Devonian)
Unadilla Formation - shale, siltstone.
Unadilla, Laurens, New Lisbon, and Gilboa Formations (Middle Devonian)
Unadilla, Laurens, New Lisbon, and Gilboa Formations - shale, siltstone, sandstone.
Undifferentiated Hamilton Group (Middle Devonian)
Undifferentiated Hamilton Group - shale, siltstone. In eastern Orange County: Skunnemunk Formation-sandstone, conglomerate; Bellvale Formation-shale, sandstone; Cornwall Shale.
Undifferentiated Lower Devonian and Silurian rocks (Lower Devonian - Silurian)
Undifferentiated Lower Devonian and Silurian rocks - in northern Ulster County: Port Ewen thru Manlius Limestones; Rondout Dolostone; Binnewater Sandstone; High Falls Shale. In Orange County: Kanhouse Sandstone; Woodbury Creek Formation-shale, sandstone; Esopus Shale; Connelly Conglomerate; Central Valley Sandstone; New Scotland Limestone thru Rondout Dolostone; Decker Limestone; Poxono Island Formation-shale, dolostone; Longwood Shale; Green Pond Conglomerate.
Undifferentiated Lower Hamilton Group (Middle Devonian)
Undifferentiated Lower Hamilton Group - shale and sandstone.
Undifferentiated Lower Hamilton Group (Middle Devonian)
Undifferentiated Lower Hamilton Group - Panther Mountain, Mount Marion, Stony Hollow, and Union Springs shales and sandstones.
Undifferentiated Medina Group and Queenston Formation (Upper Ordovician - Lower Silurian)
Undifferentiated Medina Group and Queenston Formation - Grimsby Formation-sandstones, shale; and Queenston Formation-shale, siltstone.
Undifferentiated Medina Group and Queenston Formation (Upper Ordovician - Lower Silurian)
Undifferentiated Medina Group and Queenston Formation - Grimsby Formation-sandstones, shale; and Queenston Formation-siltstone, shale.
Upper Walton Formation (Upper Devonian)
Upper Walton Formation - shale, sandstone, conglomerate.
Upper Walton Formation (Upper Devonian)
Upper Walton Formation - shale, sandstone, conglomerate.
Vernon Formation (Upper Silurian)
Vernon Formation - shale, dolostone.
Vernon Shale (Upper Silurian)
Vernon Shale
Wappinger Group (Cambrian - Lower Ordovician)
Wappinger Group - (including Fishkill limestone and dolostone): Copake Formation ?-limestone, dolostone; Rochdale Formation-limestone, dolostone; Halcyon Lake Dolostone-locally cherty; Briarcliff Dolostone; Pine Plains Formation-dolostone, shale, oolite; Stissing Formation-dolostone, shale.
Westfield Shale and Laona Siltstone (Upper Devonian)
Westfield Shale and Laona Siltstone.
West Hill and Gardeau Formations (Upper Devonian)
West Hill and Gardeau Formations - shale, siltstone; Roricks Glen Shale; upper Beers Hill Shale; Grimes Siltstone.
West Hill and Gardeau Formations (Upper Devonian)
West Hill and Gardeau Formations - shale, siltstone; Roricks Glen Shale; upper Beers Hill Shale; Grimes Siltstone.
Wiscoy Formation (Upper Devonian)
Wiscoy Formation - sandstone, shale; Hanover and Pipe Creek Shales.
Wiscoy Formation (Upper Devonian)
Wiscoy Formation - sandstone, shale; Hanover and Pipe Creek Shales.

Ohio

Allegheny and Pottsville Groups, Undivided (Pennsylvanian)
Allegheny and Pottsville Groups, Undivided - Shale, siltstone, and underclay: Shale, black, gray, and olive; clayey to silty; locally contains marine fossils; calcareous in part. Siltstone, gray, greenish and olive; clayey to sandy; thin bedded to medium bedded; locally contain marine fossils. Underclay, gray and olive; generally 3 feet or less in thickness; clayey to silty; commonly rooted and underlying coal beds; nonbedded; locally varies from flint to plastic clay. Sandstone, light to medium gray weathers to shades of yellow-brown; mostly very fine to medium grained, locally quartzose and conglomeratic in lower one-third of unit; thin to massive to cross bedded; locally calcareous; Limestone, flint and coal. Limestone, black to light gray; micritic to medium grained; locally grades into flint; thin to medium bedded to discoidal concretions containing marine fossils; locally nonmarine, micritic limestones occur beneath coal beds in upper one third of unit. Coal, mostly banded bituminous, locally cannel; thin to locally as much as 12 feet thick; generally in discrete beds but locally contain shale partings and split into multiple beds. Lateral and vertical lithic variability and gradation common. Unit as much as 700 feet thick.
Antrim Shale (Devonian)
Antrim Shale - Shale; dark brown to black; carbonaceous, thinly laminated; 0 to 230 feet thick.
Berea Sandstone and Bedford Shale, Undivided (Devonian)
Berea Sandstone and Bedford Shale, Undivided - Sandstone and shale; upper portion sandstone; brown, weathers light brown to reddish brown; thin to thick bedded, planar to lenticular bedding; minor shale interbeds; 5 to 75 feet thick, locally 100 to 125 feet thickness in Lorain, Cuyahoga, and Medina Counties; lower portion shale; gray to brown, locally reddish brown; thin to medium bedded, planar to lenticular bedding; interbedded siltstone and sandstone, ripple marks in siltstone beds; 80 to 180 feet thick, locally thin to absent where Berea Sandstone is thick.
Black Hand Sandstone Member of Cuyahoga Formation (Mississippian)
Black Hand Sandstone Member of Cuyahoga Formation - Sandstone and conglomerate; yellow-gray to white, weathers shades yellow, brown, red, and gray; very fine grained to pebbles, mostly medium to coarse grained with lenses and layers of pebbles; massive to crossbedded to laminated; grades laterally into shale and siltstone; quartzose.
Cedarville, Springfield, Euphemia, and Laurel Dolomites; Massie Shale, Undivided (Silurian)
Cedarville, Springfield, Euphemia, and Laurel Dolomite; Massie Shale, Undivided - Cedarville Dolomite, white to gray to blue gray weathers gray; abundant intercrystalline, moldic, and vuggy porosity, massive bedded, 0 to 100 feet thick. Diagnostic features include porosity, cliff-forming nature of unit, and pentamerid brachiopod fossil zone near contact with Springfield Dolomite. Springfield Dolomite, gray to tan, mottled with brownish gray, massive bedded where unweathered and layered brick-like where weathered, 5 to 10 feet thick. Euphemia Dolomite, dolomite to dolomitic limestone, gray to bluish gray, massive bedded, 5 to 15 feet thick. Diagnostic features include large, blocky bedding where weathered and cliff forming nature. Massie Shale, gray to bluish gray, minor limestone and dolomite beds, calcareous, slakes easily, planar to irregular bedding, thin to thick bedded, 0 to 10 feet thick. Diagnostic feature includes calcareous shale with limestone and dolomite. Laurel Dolomite, gray to tan, weathers brown, argillaceous to nonargillaceous, wavy bedding, thin to medium bedded, 5 to 10 feet thick. Interval ranges from 115 to 140 feet thick. Euphemia Dolomite averages 1.6 to 2.6 m in thickness. Environment of deposition was normal marine offshore, free from clastic influence; similar to Cedarville Dolomite. Unconformably overlies Massie Shale. Correlates with Bisher Formation to the southeast. Age is Wenlockian (Ausich, 1987).
Cincinnati Group as used by Wickstrom (1990) (Ordovician)
Cincinnati Group as used by Wickstrom (1990) - Shale, dolomite and limestone, interbedded. Various shades of gray; thin to medium bedded; Data from core holes. Occurs beneath glacial drift.
Clinton and Cataract Groups, Undivided (Silurian)
Clinton and Cataract Groups, Undivided - Dolomite, limestone and shale, interbedded. Various shades of gray, olive green, yellow and reddish-gray; laminated to thick bedded; argillaceous, glauconitic, pyritic, ferruginous and/or phosphatic; locally fossiliferous. Data from core holes. Occurs beneath glacial drift.
Coldwater Shale (Mississippian)
Coldwater Shale - Shale; gray; clayey thin bedded; siderite nodules common; as much as 150 feet thick.
Conemaugh Group (Pennsylvanian)
Conemaugh Group - Shale, siltstone, and mudstone: Shale, black, gray, green and red; clayey to silty; locally contains marine fossils in lower half of unit; calcareous in part. Siltstone, gray, green and red, locally variegated; clayed to sandy; thin bedded to nonbedded. Mudstone, black, gray, green, red, and yellow, variegated in part; clayey to silty; locally calcareous; commonly nonbedded. Sandstone, green-gray weathers to shades of yellow-brown; mostly very fine to medium grained, locally conglomeratic; thin to massive to cross bedded; locally calcareous. Limestone and coal; thin and discontinuous. Limestone, black, gray and green; micritic to coarse grained; thin bedded to concretionary with marine fossils common in lower half of interval; thin to medium bedded, nonmarine limestone common in upper half of unit. Coal, thin, bituminous, impure; very locally thick enough for economic development. Lateral and vertical lithic variability and gradation common. Unit as much as 500 feet thick.
Drakes, Whitewater and Liberty Formations, Undivided (Ordovician)
Drakes, Whitewater and Liberty Formations, Undivided - Drakes Formation; shale(90%) and limestone/dolomite(10%), interbedded; gray and maroon,weathers yellowish gray; planar to irregular, thin to thick bedded; 20 to 30 feet thick. Whitewater Formation, limestone(60%) and shale(40%) interbedded; gray weathers yellowish gray; irregular to wavy, thin to medium bedded; 20 to 80 feet thick. Liberty Formation, limestone(50%) and shale(50%), interbedded; gray weathers yellowish gray; planar to irregular, thin to medium bedded; 20 to 40 feet thick. Interval ranges from 60 to 150 feet in thickness. The Geological Survey of Ohio recognizes the Cincinnati Group proposed by Meek and Worthen (1865), but at this time retains it as an informal term. The unit will be formally reinstated as a lithostratigraphic term after revision of its lower boundary and minor lithologic redescription of its units are completed. The ten formations included in the group are the (ascending) Clays Ferry Formation, the Kope Formation, the Fairview Formation, the Miamitown Shale, the Grant Lake Limestone, the Arnheim Formation, the Waynesville Formation, the Liberty Formation, the Whitewater Formation, and the Drakes Formation. Six members have been identified in the course of field mapping: the Point Pleasant Tongue of the Clays Ferry, the informal Bellevue, Corryville, Mount Auburn, and Straight Creek members of the Grant Lake Limestone, and the Preachersville Member of the Drakes Formation. The Backbone Creek and Elk Creek beds are recognized as excellent stratigraphic marker beds (Shrake and others, 1988).
Drowning Creek Formation (Silurian)
Drowning Creek Formation - Limestone, and shale, interbedded; limestone, shades bluish, greenish, and yellowish gray to grayish-pink weathers light gray to shades of red; planar to irregular to nodular, thin to thick bedded; fine to very coarse grained; locally silty, dolomitic, cherty, glaconitic; moderate to abundant fossils. Shale, greenish-gray to bluish-gray weathers light gray, thin bedded; silty.
Dunkard Group (Permian and/or Pennsylvanian)
Dunkard Group - Mudstone, shale, and siltstone (60-70 percent); shades of red, yellow, olive, and/or brown in southern areas of Ohio to gray, green and black in northern areas; clayey to sandy; nonbedded to thin bedded; locally calcareous. Sandstone (25-35 percent); blue-gray weathers to shades of yellow-brown; fine grained to locally conglomeratic; thin to massive to cross bedded. Limestone and coal (5 percent): Limestone, gray, micritic, clayey to silty, thin to medium bedded in northern areas of Ohio, nodular bedded to argillaceous in southern areas. Coal, black, banded, thin, discontinuous, impure; poorly developed in southern areas of Ohio. Limestones and coals best developed in lower 90 to 200 feet. Lateral and vertical lithic variability and gradation common. Unit greater than 600 feet thick in southeast Ohio.
Estill Shale (Silurian)
Estill Shale - Shale and minor dolomite interbedded, reddish to greenish gray, weathers light gray, planar to irregular bedding, thin to thick bedded, 30 to 180 feet thick. Diagnostic features include dominance of shale and the units susceptibility to be unstable on slopes and cause landslides.
Estill Shale and Drowning Creek Formation, Undivided (Silurian)
Estill Shale and Drowning Creek Formation, Undivided - Estill Shale, reddish to greenish gray, weathers light gray, minor interbedded dolomite, planar to irregular bedding, thin to thick bedded, 30 to 180 feet thick. Forms unstable slopes susceptible to landslides. Drowning Creek Formation; dolomite with minor shale; bluish gray to gray weathers yellowish orange; argillaceous and silty in part; planar to lenticular, thin to thick bedded; 20 to 90 feet thick.
Grant Lake and Fairview Formations, Miamitown Shale, Undivided (Ordovician)
Grant Lake and Fairview Formations, Miamitown Shale, Undivided - Limestone (50%) and shale (50%), interbedded; gray to bluish-gray weathers light gray to yellowish-gray;, planar to lenticular, thin to medium bedded in lower half; wavy to irregular to nodular, thin to thick bedded in upper half; fossiliferous. Interval of shale (90%) with limestone (10%), as much as 35 feet thick, near middle of unit.
Grant Lake and Fairview Formations, Undivided (Ordovician)
Grant Lake and Fairview Formations, Undivided - Limestone and shale, interbedded; gray to bluish-gray weathers light gray to yellowish-gray; planar to lenticular, thin to medium bedded in lower half; wavy to irregular to nodular, thin to thick bedded in upper half; fossiliferous. Percent limestone increases from about 50% of interval in lower half to as much as 80% in upper half of unit.
Grant Lake Limestone and Fairview Formation, Undivided (Ordovician)
Grant Lake Limestone and Fairview Formation, Undivided - Limestone and shale, interbedded; gray to bluish-gray weathers light gray to yellowish-gray; planar to lenticular, thin to medium bedded in lower half; wavy to irregular to nodular, thin to thick bedded in upper half; fossiliferous.
Kope Formation (Ordovician)
Kope Formation - Shale(75%) and limestone(25%) interbedded; gray to bluish gray weathers light gray to yellowish gray; planar, thin to thick bedded; 200 to 260 feet thick.
Massie and Osgood Shales; Dayton and Brassfield Limestones; Laurel Dolomite; Undivided (Silurian)
Massie and Osgood Shales; Dayton and Brassfield Limestones; Laurel Dolomite; Undivided - Massie Shale; gray to bluish gray; planar to irregular, thin to thick bedded; calcareous; slakes; minor limestone and dolomite beds; 0 to 10 feet thick. Laurel Dolomite; gray to tan, weathers brown; argillaceous to nonargillaceous; wavy, thin to medium bedded; 5 to 10 feet thick. Osgood Shale, blue gray to gray weathers brown; thin to massive bedded; calcareous with minor limestone and dolomite; slakes and slumps readily in outcrop; 3 to 25 feet thick. Dayton Limestone; gray to bluish-gray weathers grayish-white; medium to thick bedded; fine grained; dolomitic; 5 to 15 feet thick. Brassfield Limestone; white to pink, locally gray to reddish brown; irregular, thin to medium bedded; coarsely crystalline; abundant pelmatozoan fossils; grayish-green glauconitic partings; cliff forming; 20 to 50 feet thick. Interval ranges from 32 to 100 feet in thickness.
Maxville Limestone; Rushville, Logan, and Cuyhoga Formations, Undivided (Mississippian)
Maxville Limestone; Rushville, Logan, and Cuyhoga Formations, Undivided - Shale, siltstone, and sandstone, interbedded; various shades of gray, yellow to brown weather similar color; sandstone, silty to granular, local stringers of quartz pebbles. Shale, clayey to silty, locally fossiliferous. Medium to dark gray, thin to thick bedded limestone locally preserved at top of interval where unit crops out in southern half of state. Lithologies percentages vary in different areas where unit crops out; laterial and vertical gradation common at regional scale.
Mississippian and Devonian Undifferentiated (Devonian and/or Mississippian)
Mississippian and Devonian Undifferentiated - Sandstone and shale, interbedded. Occurs only in Serpent Mound Impact Structure.
Monongahela Group (Pennsylvanian)
Monongahela Group - Shale, siltstone, and mudstone; black, red, gray and green to variegated red and yellow in the southeastern areas of Ohio; clayey to sandy; nonbedded to thin bedded; locally calcareous. Sandstone, greenish-gray weathers to shades of yellow-brown, silty to locally conglomeratic; thin to massive to cross bedded; locally calcareous. Limestone, gray, micritic, clayey to silty, thin to medium bedded; generally more common in middle and lower portions of unit. Coal, banded, bituminous, thin to as much as 8 feet thick in central and northern areas, thinner to absent in southeastern Ohio. Lateral and vertical lithic variability and gradation common. Unit as much as 350 feet thick.
Ohio Shale (Devonian)
Ohio Shale - Shale; brownish black to greenish gray, weathers brown; carbonaceous to clayey, laminated to thin bedded, fissile parting; carbonate and/or siderite concretions in lowermost 50 feet; petroliferous odor; 250 to 500+ feet thick. Includes Olentangy Shale south of central Delaware Co.
Olentangy Shale (Devonian)
Olentangy Shale - Shale; greenish gray to medium gray; clayey; laminated to thin bedded; thin beds of brownish-gray shale in upper 2/3, limestone nodules in lower 1/3; 20 to 55 feet thick.
Ordovician Undifferentiated (Ordovician)
Ordovician Undifferentiated - Shale, dolomite, and limestone, interbedded; various shades of gray; thin to medium bedding, structurally disturbed. Occurs only in Serpent Mound Impact Structure.
Peebles Dolomite, Lilley and Bisher Formations, Undivided (Silurian)
Peebles Dolomite, Lilley Formation, Bisher Formation, Undivided - Peebles Dolomite, bluish gray weathers light gray; planar to irregular, thick to massive bedded; 0 to 120 feet thick; vuggy to cavernous porosity; cliffs former. Lilley Formation, dolomite with minor limestone, chert, and shale; bluish gray to gray weathers reddish gray to gray; planar to irregular, thin to thick bedded; 20 to 80 feet thick; fossiliferous. Bisher Formation, dolomite with minor shale; bluish gray to gray weathers yellowish-orange; argillaceous and silty in part; planar to lenticular, thin to thick bedded; 20 to 90 feet thick; Interval ranges from 80 to 160 feet in thickness. Peebles Dolomite overlies Lilley Formation and underlies Greenfield Dolomite, Hillsboro Sandstone, or Ohio Shale in southern OH. Age is Silurian (Wenlockian and Ludlovian) (Rexroad and Kleffner, 1984). Wenlockian age of the Lilley Formation is based on 10 species of conodont fauna. The Lilley Formation, Lilley-Peebles transition unit, and the Peebles Dolomite compose the upper Niagaran sequence along the east flank of the Cincinnati arch in southern OH. The Lilley consists of two main lithologies: 1) gray to blue gray, fine-grained argillaceous, variably fossiliferous uneven- to thin-bedded dolomite with dolomitic shale partings and 2) light-gray, medium to coarse-grained fossiliferous dolomite. Thickness averages 15 m in Adams and southeastern Highland Cos. and thickens to 24 m in western and northwestern Highland Co. Eustatic sea-level fall in early to middle Wenlockian is proposed as the cause for shoaling during deposition. Underlies Peebles Dolomite and overlies Bisher Formation (Kleffner, M.A., 1990).
Plum Brook Shale (Devonian)
Plum Brook Shale - Shale and argillaceous limestone; gray; thin bedded fossiliferous; 0 to 40 feet thick.
Point Pleasant Formation (Ordovician)
Point Pleasant Formation - Limestone (60%) and shale (40%) interbedded; gray to bluish gray weathers light gray; planar to lenticular, thin to medium bedded; 0 to 80 feet thick.
Preacherville Member of the Drakes Formation, Waynesville and Arnheim Formation, Undivided (Ordovician)
Preacherville Member of the Drakes Formation, Waynesville and Arnheim Formation, Undivided - Shale, limestone, and dolomite, interbedded; gray to maroon in upper part, weathers yellowish-gray to light-gray; planar to irregular to wavy to nodular, thin to thick bedded; shale increases upward.
Salina Group (Silurian)
Salina Group - Dolomite, gray, yellow-gray to olive-gray, laminated to thin bedded; occasional thin bed and laminae of dark gray shale and anhydrite and/or gypsum; brecciated zones in part.
Sunbury and Bedford Formations, Undivided (Devonian and/or Mississippian)
Sunbury and Bedford Formations, Undivided - Shale and siltsone; shale, black to brownish-black, carbonaceous in upper one third of interval, gray to bluish-gray, clayey with occasional siltstone lamina and thin beds in lower two-thirds of interval.
Sunbury Shale, Berea Sandstone, and Bedford Shale, Undivided (Devonian and/or Mississippian)
Sunbury Shale, Berea Sandstone, and Bedford Shale, Undivided - Shale and sandstone; upper 10 to 50 feet shale; black to brown, weathers light brown; carbonaceous; thin, planar bedding. Underlain by 10 to 50 feet sandstone; brown, weathers light brown to reddish brown; thin to thick bedded, planar to lenticular bedding; minor shale interbeds. Basal 80 to 100 feet shale and interbedded sandstone; gray to brown, weathers light gray to light brown; thin to medium bedded, planar to lenticular bedding; thick. Interval thickness ranges from 100 to 200 feet.
Traverse Group (Devonian)
Traverse Group - Dolomite and shale interbedded with limestone; upper part dolomite; gray to light brown; thin to medium bedded; abundant chert; lower part shale interbedded with limestone; olive gray; thin to medium bedded; very fossiliferous; as much as 170 feet thick.
Tymochtee and Greenfield Formations, Undivided (Silurian)
Tymochtee and Greenfield Formations, Undivided - Dolomite, olive-gray to yellowish- brown, thin to massive bedded, upper two-thirds commonly contains brownish-black to gray shale laminae; locally developed brecciated zones in lower one third.
Waynesville and Arnheim Formations, Undivided (Ordovician)
Waynesville and Arnheim Formations, Undivided - Waynesville Formation, shale(70%) and limestone(30%) interbedded; gray to bluish gray weathers light gray; planar to irregular, thin to thick bedded; 90 to 120 feet thick. Arnheim formation, shale(60%) and limestone(40%) interbedded; gray to bluish gray weathers light gray; planar, wavy, irregular, to nodular (in upper portion), thin to thick bedded; 50 to 100 feet thick. Contains multiple sedimentary cycles consisting of the alternation of shale and limestone displaying planar to irregular bedding with limestone and shale exhibiting wavy to nodular bedding. Ranges from 140 to 220 feet. The Geological Survey of Ohio recognizes the Cincinnati Group proposed by Meek and Worthen (1865), but at this time retains it as an informal term. The unit will be formally reinstated as a lithostratigraphic term after revision of its lower boundary and minor lithologic redescription of its units are completed. The ten formations included in the group are the (ascending) Clays Ferry Formation, the Kope Formation, the Fairview Formation, the Miamitown Shale, the Grant Lake Limestone, the Arnheim Formation, the Waynesville Formation, the Liberty Formation, the Whitewater Formation, and the Drakes Formation. Six members have been identified in the course of field mapping: the Point Pleasant Tongue of the Clays Ferry, the informal Bellevue, Corryville, Mount Auburn, and Straight Creek members of the Grant Lake Limestone, and the Preachersville Member of the Drakes Formation. The Backbone Creek and Elk Creek beds are recognized as excellent stratigraphic marker beds (Shrake and others, 1988).

Oklahoma

Ada Group or Ada Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late)
ENID- "Ada Group"- Mainly shale with many limestone layers that are thinner and pinch out southward, where fine-grained sandstones are thicker and more numerous. Near Kansas border, group includes (descending): "Auburn shale" (50 feet thick) at top, underlain by "Wakarusa Limestone," IPaw (2 feet thick), unnamed shale (40 feet thick), "Rulo Limestone" (3 feet thick), unnamed shale (18 feet thick), "Happy Hollow Limestone" (2 feet thick), unnamed shale and sandstone (60 feet thick), "Bird Creek Limestone," IPab (2 feet thick; called "Church Limestone" in Kansas), "Severy-Aarde Shale" (70 feet thick), "Turkey Run Limestone," IPat (2 feet thick; called "Coal Creek Limestone" in Kansas), unnamed shale (30 feet thick), "Pearsonia Limestone" (3 feet thick), unnamed shale (15 feet thick), "Little Hominy Limestone" (22 feet thick), "Deer Creek Limestone (15 feet thick), unnamed shale (10 feet thick), "Plummer Limestone" (2 feet thick), unnamed shale (35 feet thick), and "Beil Limestone Member" (10 feet thick) of "Lecompton Limestone" at base. Total thickness, about 400 feet (120 m). OKLAHOMA CITY- "Ada Group"- Mostly orange-brown fine-grained sandstone and red-brown to gray shale; grades southward into chert conglomerates. Includes the following thin limestone beds and shale units north of North Canadian River (descending): "Auburn Shale" (80 feet thick), "Wakarusa Limestone," IPaw (1 to 6 feet thick), unnamed shale (95 feet thick), "Bird Creek Limestone," IPab (1 to 9 feet thick), "Severy-Aarde Shale" (45 feet thick), "Turkey Run Limestone," IPat (1 foot thick), unnamed shale (45 feet thick), and "Lecompton Limestone" (1.5 to 10 feet thick), at base. Total thickness of group ranges from 100 feet in south to 280 feet in north. ARDMORE-SHERMAN- "Ada Formation"- (= Collings Ranch Conglomerate) Shale, red-brown to gray, bituminous sandstone, and limestone conglomerate; thickness, 100 to 1,400 feet (subsurface), decreasing southward.
Arkansas Novaculite (Phanerozoic | Paleozoic | Devonian-Late)
ARDMORE-SHERMAN- Shale, black, cherty, with much novaculite; thickness, 230 to375 feet. Occurs in the OUACHITA MNTS
Arkansas Novaculite (Phanerozoic | Paleozoic | Silurian Devonian(?) Carboniferous Mississippian-Early )
McALESTER TEXARKANA- Chert, fine- to very fine-grained, gray, green, tan, black, white, and pink, with interbedded black to gray shale in 1-to 18-inch beds; some interbedded conglomerates and in places a basal conglomerate; upper part has been determined to be Mississippian in age and lower part to be Early Silurian, on basis of examination of palynomorphs from Potato Hills; thickness, 600 feet or more. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT.
Atoka, Bloyd and Hale Formations Undifferentiated (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early Pennsylvanian-Middle)
FORT SMITH- IPu Undifferentiated. Atoka, Bloyd, and Hale Formations. IPat "Atoka Formation," shale and sandstone, IPbh "Bloyd Formation," shale and limestone; and "Hale Formation," limestone and sandstone.
Atoka Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- IPat "Atoka Formation," shale, siltstone, sandstone, and thin limestone. FORT SMITH- IPat "Atoka Formation," shale and sandstone. ARDMORE-SHERMAN- Shale, dark-gray, and sandstone, buff to white, fine- to coarse-grained, with some chert conglomerates; thickness, 800 to 3,000 feet. McALESTER TEXARKANA- Shale, gray to tan, illitic, chloritic, with many sandstones, fine- to coarse-grained, quartzose, micaceous, well- to poorly sorted; "Fanshawe" and "Red Oak Sandstones" in middle and "Spiro Sandstone" at base; thickness, 3,000 to 10,000 feet, increasing southeastward in subsurface, south of growth faults.
Barnsdall Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- Formation is mainly fine- to medium-grained sandstone, overlain by shale. At top is a thick shale, with "Okesa Sandstone Member" in middle and "Birch Creek Limestone" (called "South Bend Limestone") at base. Birch Creek extends southward from Kansas border to Township 23 N., where limestone grades into overlying Okesa Sandstone. South of Township 23 N., Okesa grades downward into underlying "Torpedo Sandstone" and underlying Wann Formation. Total thickness ranges from 45 to 200 feet (14 to 60 m). OKLAHOMA CITY- Mostly fine-grained sandstone overlain by shale; may grade northward into "Wann Formation". Thickness ranges from about 80 to 200 feet.
Belle City Formation or Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- "Belle City Limestone"-Consists of two fossiliferous limestone units with an intervening fossiliferous shale. Thickness ranges from 12 to 20 feet; present in southern part of area only, where it is below "Hilltop Formation". ARDMORE-SHERMAN- 'Belle City Formation"-Limestone, gray to buff, dense, in 2 beds each 2 to 3 feet thick, with interbedded dark-gray shale, 10 to 20 feet thick.
Bigfork Chert (Phanerozoic | Paleozoic | Ordovician-Middle)
ARDMORE-SHERMAN- Limestone, gray, and dark-gray to black chert; thickness, 575 feet. Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- Chert, dark-gray to black, with interbedded graptolitic black shales and fossiliferous gray to black cherty limestones; contains asphaltite seams; erodes into a mappable escarpment; thickness, 600 to 800 feet. (Same as Viola Limestone in Arbuckle Mountains.) Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
Bison Formation or Bison Shale (Phanerozoic | Paleozoic | Permian )
WOODWARD- "Bison Formation"- Mostly orange-brown to greenish-gray fine-grained sandstone. Thickness ranges up to 120 feet. ENID- "Bison Formation"-Mainly red-brown shale and greenish-gray and orange-brown calcitic siltstone with minor sandstone in Garfield County. Thickness, about 120 feet (35 m). (Hennessey Group) CLINTON- "Bison Formation," Pbi, is exposed as orange-brown and greenish-gray, fine-grained sandstone and siltstone. The Bison is gradational southward into reddish-brown shale; it thins southward and is about 120 feet thick. OKLAHOMA CITY- "Bison Formation"-Mostly red-brown shale; grades northward into many thin greenish-gray calcitic siltstones and some orange-brown fine-grained sandstones and siltstones. "Reeding Sandstone Bed" at base. Thickness ranges from 95 feet in south to 120 feet in north. (Hennessey Group). ARDMORE-SHERMAN- "Bison Shale"-Shale, gray to red-brown, calcareous, blocky; thickness, 50 to 90 feet, decreasing southward. (Hennessey Group)
Blaine Formation (Phanerozoic | Paleozoic | Permian )
WOODWARD- Alternating cyclic sequence of 3 or 4 massive gypsum beds with red-brown shales, generally with a named dolomite at the base of each gypsum, and a greenish-gray shale at the base of each dolomite. The named unmapped sequence is (ascending) "Cedar Springs Dolomite, Medicine Lodge Gypsum," shale, "Magpie Dolomite, Nescatunga Gypsum," shale, "Altona Dolomite, Shimer Gypsum," shale, and"Haskew Gypsum" at top. Thickness ranges up to 90 feet, with the shales being thinner northward. CLINTON- "Blaine Formation," Pb, 3 to 4 gypsum and dolomite beds, about 100 to 200 feet thick, separated by reddish-brown shale. Gradational southward and eastward into Chickasha Formation. OKLAHOMA CITY- Mostly thin gypsums with thin dolomites below each gypsum, interbedded with red-brown shale; grades southward into "Chickasha Formation". Thickness, 50 to 75 feet. (El Reno Group)
Blaylock Sandstone (Phanerozoic | Paleozoic | Silurian)
McALESTER TEXARKANA- Sandstone, greenish-gray, fine grained, well indurated, alternating with dark-gray to brown phyllites and shales in lower 100 feet; occurs only in Broken Bow Uplift and adjacent area; thickness, 670 to 804 feet, with maximum thickness in Arkansas 1,500 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
Bloyd and Hale Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
TULSA- "Bloyd Formation," limestone and shale. "Hale Formation," limestone and sandstone. FORT SMITH- IPbh "Bloyd Formation," shale and limestone; and "Hale Formation," limestone and sandstone.
Boggy Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Shale, sandstone, and coal. FORT SMITH- Shale, sandstone, and coal; includes Bluejacket Sandstone Member at base. ARDMORE-SHERMAN- Shale and sandstone, blue-gray to brown, fine- to coarse- grained, with some thin limestone lenses and a coal bed 2.5 feet thick about 400 feet above base. Thickness, 1,250 to 2,800 feet. "Bluejacket Sandstone," IPbj, at base, 8 to 12 feet thick, with 2-foot "Secor coal" 50 feet above top of Bluejacket. (Lower Franks Conglomerate) McALESTER TEXARKANA- Shale, brown, to blue-gray, illitic, chloritic, with many sandstones, fine- to coarse-grained, micaceous, quartzose, moderately to well-indurated, with "Secor coal" about 50 feet above base; thickness, 2,140 to 4,000 feet, increasing eastward.
Bromide + Tulip Creek and McLish Formations (Phanerozoic | Paleozoic | Ordovician-Middle)
ARDMORE-SHERMAN- Limestone, buff; shale, grayish-green; and sandstone, brown to white, fine- to medium-grained: approximate sequence of rocks in each formation, from top to bottom. Thickness, 750 to 1,400 feet, thinning eastward. (Simpson Group) Occurs in the ARBUCKLE MTNS
Caddo Formation (Phanerozoic | Mesozoic | Cretaceous-Early )
ARDMORE-SHERMAN-Limestones, marls, and shales; 150 feet thick. Subdivided into "Fort Worth Limestone" at top and "Duck Creek Limestone" below. McALESTER TEXARKANA- Limestones, white to cream, silty, alternating with gray shales, with "Texigryphaea washitaensis;" 7-foot bed at top (Fort Worth equivalent) and blue-gray silty shales and limestones below with "Texigryphaea navia" (Duck Creek equivalent); thickness, 150 feet. Ouachita Mountain uplift; S. OK folded belt province
Calvin Sandstone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- Medium-grained, thin-bedded to massive sandstone nd silty shale. Thickness ranges from 230 to about 440 feet. FORT SMITH- Shale and sandstone ARDMORE-SHERMAN- Sandstone, brown, medium-grained, with some gray shale; thickness, 40 to 320 feet, thinner southward.
Cedar Hill Sandstone (Phanerozoic | Paleozoic | Permian )
WOODWARD- Orange-brown to greenish-gray fine-grained sandstone and siltstone, with some red-brown shale. Thickness ranges up to 180 feet, with more sandstone to the north and more shale to the south. ENID- Mainly orange-brown, fine-grained quartzose sandstone. Thickness about 180 feet (55 m). (El Reno Group) CLINTON- "Cedar Hill Sandstone," Pch, greenish-gray sandstone and reddish-brown shales; thickness, about 180 feet; gradational southward into Duncan Sandstone. OKLAHOMA CITY- Lenticular beds of orange-brown fine-grained sandstone and red-brown shale; lower part grades southward into "Duncan Sandstone". "Piedmont Sandstone Bed" at base. Thickness, 180 feet (only lower 80 feet exposed in mapped area). (El Reno Group)
Chanute Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- Mainly fine-grained micaceous sandstone and coarse-grained, crossbedded sandstone separated by shale. Locally Chanute contains thin coal seams. Thickness ranges from about 10 to 150 feet (3 to 45 m). TULSA- Thin- to thick-bedded, fine- to coarse-grained sandstone and shale. OKLAHOMA CITY- Mainly fine- to medium-grained sandstone 3 to 20 feet thick, overlain by shale 20 to 80 feet thick. Total thickness ranges from about 25 to 90 feet.
Chattanooga + Fernvale + Fite + Tyner + Burgen + Cotter Formations (Phanerozoic | Paleozoic | Ordovician-Early Ordovician-Middle(?) Ordovician-Late(?) Silurian(?) Devonian(?) Carboniferous Mississippian-Early(?) Mississippian-Middle(?) Mississippian-Late)
TULSA- "Chattanooga Formation," shale and minor sandstone. "Fernvale Formation," limestone. "Fite Formation," limestone "Tyner Formation," shale and dolomite "Burgen Sandstone," sandstone and minor dolomite and shale. "Cotter Formation," dolomite and minor sandstone.
Chickasha Formation (Phanerozoic | Paleozoic | Permian )
WOODWARD- The "Chickasha Formation" member of Flower Pot Shale (Pc) is a deltaic tongue of red-brown to greenish-gray to orange-brown cross-bedded mudstone conglomerate, siltstone, shale, and fine-grained sandstone, about 30 feet thick, in the middle of the Flowerpot Shale, pinching out northward. CLINTON- "Chickasha Formation," Pc, reddish-brown to maroon mudstone conglomerate with some shale, silstone, and fine- to coarse-grained sandstone; thickness, about 600 feet; gradational northward and westward into the Flowerpot Shale and the Blaine Formation and westward into Dog Creek Shale. OKLAHOMA CITY-Variegated mudstone conglomerate and red-brown to orange- brown silty shale and siltstone, with minor amounts of orange-brown fine-grained sandstone; upper part grades northward into "Dog Creek Shale", "Blaine Formation", "Flowerpot Shale", and upper part of "Cedar Hills Sandstone"; lower part grades into "Duncan Sandstone". Thickness, about 100 feet near Chickasha and 300 feet near Okarche. (El Reno Group) ARDMORE-SHERMAN- Mudstone conglomerate, siltstone, and sandstone, red-brown; thickness, 100 to 200 feet, decreasing southeastward. (El Reno Group)
Cloud Chief Formation (Phanerozoic | Paleozoic | Permian )
WOODWARD- Red-brown and greenish-gray shale and siltstone with some orange-brown fine-grained sandstone and siltstone. At base are two or more thin, pink to maroon to greenish-gray dolomite beds and (or) gypsum beds ("Moccasin Creek Bed") eroding into a mappable escarpment. About 25 feet above the base is a white to light-gray dolomite ("Day Creek Bed") not mapped. Thickness ranges up to 160 feet, with top eroded in many places. CLINTON- Reddish-brown to orange-brown shale, interbedded with siltstone and sandstone in the middle part and some dolomite and much gypsum in lower part; thickness about 400 feet, thinning northward to about 175 feet. The "Moccasin Creek Gypsum Member" is at the base. LAWTON- Represented in this area by the "Moccasin Creek Gypsum Member," which is about 30 feet (9 m) thick.
Coffeyville and Checkerboard Formations or Checkerboard Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- "Coffeyville Formation" is mainly shale interbedded with fine-to medium-grained sandstone. Locally formation contains thin coal seams. Thickness ranges from 175 to 470 feet (50 to 140 m). Underlying "Checkerboard Limestone" is crystalline limestone 2 to 15 feet (1 to 5 m) thick. TULSA- "Coffeyville Formation," shale and thin-bedded sandstone. "Checkerboard Formation," limestone and some shale. OKLAHOMA CITY- "Coffeyville Formation," mainly shale interbedded with fine- to medium-grained sandstone locally containing chert and limestone conglomerate and thin coal seams; thickness, 150 to 470 feet. Underlying "Checkerboard Limestone," crystalline limestone 2.5 to 5 feet thick.
Coffeyville or Francis Formation (restricted) (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ARDMORE-SHERMAN- Shale, dark-blue, 20 to 70 feet thick, with "DeNay Limestone," yellow, massive, 2 to 6 feet thick at base, and 20 feet or more of buff fine- to coarse-grained sandstone and chert conglomerate at top. (Upper Franks Conglomerate)
Collier Shale (Phanerozoic | Paleozoic | Cambrian-Furongian Ordovician-Early)
McALESTER TEXARKANA- Shale and phyllite, dark-gray to black, with much limestone, some granitic and arkosic pebbles, many quartz and orthoclase pegmatities, and some galena and sphalerite; contains Lower Ordovician conodonts; base covered; exposed thickness, 200 feet. Viersen and Cochran's 25-1 Weyerhaeuser well (9-8-70), spudded in upper Collier to total depth of 10,019 feet in Southeast quarter of Northwest quarter of section 25, Township 5 South, Range 23 East, penetrated dark-gray to black phyllites, quartzites, and dolomitic marble without reaching basement (Goldstein, 1975). Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
Colorado Group (Phanerozoic | Mesozoic | Cretaceous-Early )
CIMARRON- includes: Greenhorn Limestone: Gray fossiliferous limestone and calcareous shale. Graneros Shale: Dark-gray shale.
Dakota Group (Phanerozoic | Mesozoic | Cretaceous-Early )
CLINTON- Outliers of the "Kiowa Formation," Kk, dark-gray shale with some thin beds of fossiliferous tan limestone, range in thickness from a few feet to about 20 feet. Associated in some places is a 5- to 10-foot, gray to brown, coarse-grained sandstone and conglomerate assigned to the overlying "Dakota Group," Kd, (lower sandstone part).
Dakota Sandstone (Phanerozoic | Mesozoic | Cretaceous-Early )
CIMARRON- Buff to light-brown, fine- to medium-grained, thin bedded to massive sandstone with interbedded shales.
Deese Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ARDMORE-SHERMAN- Member of Glenn Fm, mainly massive sandstone, conglomerate and shale. Base of "Confederate Limestone" down to top of "Otterville Limestone;" thickness, 9,700 feet. Occurs in the ARDMORE BASIN
Delaware Creek Shale (Phanerozoic | Paleozoic | Carboniferous Mississippian)
ARDMORE-SHERMAN- 1. Shale, dark-gray to black, fissile, calcareous; thickness, 160 to 750 feet, decreasing northward. Occurs in the ARBUCKLE MTNS 2. Shale, dark-gray to black fissile; thickness 525 feet. Occurs in the OUACHITA MTNS McALESTER TEXARKANA- Shale, black, laminated, with limestone, siderite, and phosphatic concretions, and with greenish-gray silty glauconitic shale at base; thickness, approximately 500 feet. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.
DeQueen Limestone (Phanerozoic | Mesozoic | Cretaceous-Early )
McALESTER TEXARKANA- Limestone and marl, blue- to pinkish- to yellowish-gray, locally siliceous, interbedded with varicolored calcareous shales; basal limestone conglomerate in places where unconformable upon Ouachita rocks but absent where conformable on Holly Creek Formation; contains 80 feet of gypsum and anhydrite in subsurface; thickness, 38 feet, lensing out to 1 foot westward but thickening to 190 feet southeastward in subsurface.
Dewey Formation or Dewey Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- "Dewey Limestone"- Mainly medium-crystalline limestone and shale. Thickness ranges from 0 to 60 feet (0 to 18 m). TULSA- "Dewey Formation"- Limestone and some shale. (Mapped with the Chanute formation south of Bartlesville) OKLAHOMA CITY- "Dewey Limestone"- Mainly sandy limestone or calcareous sandstone containing limestone lenses 1.5 to 20 feet thick, overlain by shale 5 to 50 feet thick. Total thickness ranges from 20 to 60 feet.
Dexter Member of Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late )
ARDMORE-SHERMAN- sandstone, shale, and lignite, moderately to weakly indurated, about 100 feet thick.
Dockum Group (Phanerozoic | Mesozoic | Triassic-Late )
CIMARRON- Upper shale unit: Varicolored siltstone or claystone, conglomerate, fine-grained sandstone, and limestone. Lower sandstone unit: Varicolored, fine- to coarse-grained sandstone with some clay and interbedded shale.
Dog Creek Shale (Phanerozoic | Paleozoic | Permian )
WOODWARD- Red-brown shale and silty shale, with gypsum, dolomite, and orange-brown sandstone. In upper part are many thin,dense light-gray dolomite beds, the basal one of which is named "Southard Bed" (unmapped); in lower part is much satin-spar gypsum with a greenish-gray dolomite at top termed "Watonga Bed" (unmapped). Thickness ranges from 30 feet or less at Kansas border to 100 feet in southern part of area. CLINTON- "Dog Creek Shale," Pdc, reddish-brown shale with thin beds of siltstone and dolomite; thickness, about 220 feet; gradational eastward into the Chickasha Formation. OKLAHOMA CITY- Mostly red-brown silty shale and some fine-grained sandstone. Contains one or two layers of thin dolomite (or gypsum) in lower part; basal part grades southward into "Chickasha Formation". Thickness averages about 200 feet. (El Reno Group) LAWTON- "Dog Creek Shale," Pdc, reddish-brown silty shale, 85 to 190 feet (26 to 58 m) thick. (El Reno Group) ARDMORE-SHERMAN- Shale, red-brown, blocky, silty, weakly indurated, gradational southward into "Chickasha Formation;" thickness, 0 to about 130 feet. (El Reno Group)
Dornick Hills Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ARDMORE-SHERMAN- Series of tan shales with limestones, limestone conglomerate and sandstone. Top of "Otterville Limestone" down to base of "Lake Ardmore Sandstone;" thickness 1,800 feet. Occurs in the ARDMORE BASIN
Doxey Formation or Doxey Shale (Phanerozoic | Paleozoic | Permian )
WOODWARD- "Doxey Formation"- Red brown shale and siltstone, with greenish-gray calcareous siltstone at base. Exposed thickness is 30 feet, with top eroded. CLINTON- "Doxey Shale"- Reddish-brown, silty shale and siltstone; thickness, about 190 feet.
Duncan Sandstone (Phanerozoic | Paleozoic | Permian )
CLINTON- "Duncan Sandstone," Pd, light-gray and reddish-brown, cross-bedded, fine-grained sandstone and mudstone conglomerate with some interbedded yellowish-gray and reddish-brown shales; thickness, about 200 feet; gradational into the Cedar Hills Sandstone northward and into the Flowerpot Shale northward and westward. OKLAHOMA CITY- Mainly red-brown to orange-brown fine-grained sandstone, with some mudstone conglomerate and shale; grades northward into "Cedar Hills Sandstone" and "Chickasha Formation". Thickness, 450 feet near Chickasha, 300 feet near Oklahoma City, and 100 feet or more near Okarche. (El Reno Group) ARDMORE-SHERMAN- Sandstone, white to buff, fine- to coarse-grained, moderately indurated, with interbedded mudstone conglomerates and siltstones; thickness, 100 to 400 feet, decreasing southeastward. (El Reno Group)
Eagle Ford Formation (Phanerozoic | Mesozoic | Cretaceous-Late )
ARDMORE-SHERMAN- Shale, dark-gray, plastic; thickness, about 50 feet; top eroded.
El Reno Group (Phanerozoic | Paleozoic | Permian )
CLINTON- Primarily evaporites and reddish-brown shale, with deltaic clastics to the southeast. Where separate formations have not been distinguished, the "El Reno Group" is mapped as Per; El Reno Group. Includes: "Dog Creek Shale," Pdc, reddish-brown shale with thin beds of siltstone and dolomite; thickness, about 220 feet; gradational eastward into the Chickasha Formation. "Blaine Formation," Pb, 3 to 4 gypsum and dolomite beds, about 100 to 200 feet thick, separated by reddish-brown shale. Gradational southward and eastward into Chickasha Formation. "Flowerpot Shale," Pf, reddish-brown shale containing several salt and gypsum beds in the upper part. Thickness, about 300 to 450 feet; gradational southward and eastward into Chickasha Formation and Duncan Sandstone. "Cedar Hill Sandstone," Pch, greenish-gray sandstone and reddish-brown shales; thickness, about 180 feet; gradational southward into Duncan Sandstone. "Chickasha Formation," Pc, reddish-brown to maroon mudstone conglomerate with some shale, silstone, and fine- to coarse-grained sandstone; thickness, about 600 feet; gradational northward and westward into the Flowerpot Shale and the Blaine Formation and westward into Dog Creek Shale. "Duncan Sandstone," Pd, light-gray and reddish-brown, cross-bedded, fine-grained sandstone and mudstone conglomerate with some interbedded yellowish-gray and reddish-brown shales; thickness, about 200 feet; gradational into the Cedar Hills Sandstone northward and into the Flowerpot Shale northward and westward. LAWTON- Primarily evaporites and reddish-brown shale, with deltaic clastics to the east. In the eastern part of the quadrangle, separate formations have not been distinguished, and the "El Reno Group" is mapped as Per; in the western part of the quadrangle, the group has been mapped as four separate formations. "El Reno Group undifferentiated," Per, in northeastern part of the quadrangle, includes "Chickasha Formation" sandstone, shale, and siltstone, 400 to 580 feet (120 to 180 m) thick-and underlying "Duncan Sandstone" (equivalent to San Angelo Sandstone)-sandstone with some shale, 100 to 250 feet (30 to 76 m) thick.
Fairmont Shale (Phanerozoic | Paleozoic | Permian )
WOODWARD- Red-brown blocky shale with some greenish-gray calciti siltstones. Thickness ranges up to 160 feet. ENID- Mainly red-brown shale with many thin layers of calcitic siltstone in upper 60 feet (18 m). Thickness, about 150 feet (45 m). (Hennessey Group) OKLAHOMA CITY- Red-brown blocky shale; grades into "Garber Sandstone" at base. Thickness, 30 feet at Oklahoma City, 110 feet near Purcell, and 120 feet near Kingfisher. (Hennessey Group) ARDMORE-SHERMAN- Shale, red-brown, blocky; thickness, 40 to 80 feet, decreasing southward. (Hennessey Group)
Flowerpot Shale (Phanerozoic | Paleozoic | Permian )
WOODWARD- Red-brown silty shale with some thin gypsum and dolomite beds in upper 50 feet and fine-grained sandstones in upper part to north. The middle and upper parts contain 50 feet or more of rock salt in the immediate subsurface, giving origin to the Ferguson Salt Plain in Blaine County and the Big and Little Salt Plains in Woods and Harper Counties on the Cimarron River. Thickness ranges from 180 feet in north part to 430 feet in south part. The "Chickasha Formation" (Pc) is a deltaic tongue of red-brown to greenish-gray to orange-brown cross-bedded mudstone conglomerate, siltstone, shale, and fine-grained sandstone, about 30 feet thick, in the middle of the Flowerpot Shale, pinching out northward. CLINTON- "Flowerpot Shale," Pf, reddish-brown shale containing several salt and gypsum beds in the upper part. Thickness, about 300 to 450 feet; gradational southward and eastward into Chickasha Formation and Duncan Sandstone. OKLAHOMA CITY- Mostly red-brown silty clay shale with stringers of gypsum (satin spar and selenite); grades southward into "Chickasha Formation". Thickness, 20 to 40 feet. (El Reno Group) LAWTON- "Flowerpot Shale," Pf, reddish-brown and greenish-gray shale, interbedded with greenish-gray siltstone; thickness, about 175 to 195 feet (53 to 59 m).
Fort Scott Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Limestone and shale. (Mapped with the Labette Formation south of Bird Creek inTulsa County)
Garber Sandstone (Phanerozoic | Paleozoic | Permian )
ENID- Mostly orange-brown, fine- to medium-grained quartzose sandstone and conglomerate, grading northward into shale and calcitic siltstone. Thickness, about 600 feet (180 m). (Sumner Group) OKLAHOMA CITY- Mostly orange-brown to red-brown fine-grained sandstone, irregularly bedded with red-brown shale and some chert and mudstone conglomerate. Thickness ranges from 150 feet in south to 400 feet or more in north. (Sumner Group) LAWTON- "Garber Sandstone," Pg, reddish-brown, fine-grained sandstone and mudstone conglomerate, 160 to 210 feet (49 to 64 m) thick, containing a basal sandstone, the "Asphaltum Sandstone Bed," about 10 to 60 feet (3 to 18 m) thick.(Sumner Group) ARDMORE-SHERMAN- Sandstone, red-brown, fine- to coarse-grained; thickness, about 110 to 150 feet, including Fairmont Shale west of Elmore City, Garvin County
Goddard Shale (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late)
ARDMORE-SHERMAN- 1. Mainly shale, gray, limonitic; thickness, 3,600 feet in Ardmore Basin, 240-450 feet on Lawrence uplift. In places includes "Rod Club" and "Overbrook Sandstones" and "Union Valley Formation-Wapanucka" shale. Occurs in the ARBUCKLE MTNS 2. Shale, gray, limonitic; estimated thickness, 500 feet, but may be 2,500 Occurs in the OUACHITA MNTS McALESTER TEXARKANA- Shale, gray to black, with some sandstones and ironstone concretions; thickness, 500 feet or more. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT
Hartshorne Sandstone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ARDMORE-SHERMAN- Sandstone, gray to white, medium- to coarse-grained with interbedded middle gray shale and "Lower Hartshorne coal;" thickness, 10 to 300 feet. McALESTER TEXARKANA- Sandstone, tan to gray to white, fine- to coarse-grained, micaceous, quartzose, moderately to well-indurated, with some interbedded gray shale; "Lower Hartshorne coal" in middle and "Upper Hartshorne coal" at top; thickness, 100 to 350 feet, increasing eastward.
Hennessey Group (Phanerozoic | Paleozoic | Permian )
CLINTON- Reddish-brown shale with some thin, greenish-gray siltstone and orange-brown sandstone and siltstone beds; thickness, about 500 feet. The "Hennessey Group" is not subdivided in the southern part of the Clinton quadrangle; in the northeastern corner of the quadrangle, the upper part of the "Bison Formation," Pbi, is exposed as orange-brown and greenish-gray, fine-grained sandstone and siltstone. The Bison is gradational southward into reddish-brown shale; it thins southward and is about 120 feet thick. LAWTON- "Hennessey Group," Phy, reddish-brown to gray shale with some tan sandstones, 130 to 200 feet (40 to 60 m) thick (locally unconformable on Cambrian igneous rocks).
Hilltop Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- Mainly shale, grading upward into massive siltstone and fine- grained sandstone; grades northward into "Barnsdall Formation", "Chanute Formation", and "Dewey Limestone". Thickness ranges from 0 to 200 feet. ARDMORE-SHERMAN- Shale, blue-gray to red-brown, with buff siltstones and fine-grained sandstones at top; thickness, about 70 feet.
Hogshooter Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Limestone and some shale. (Mapped with the Nellie Bly Formation south of Bartlesville)
Holdenville and Lenapah Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- "Holdenville Formation," shale and minor sandstone and limestone. "Lenapah Formation", limestone and shale. (Map unit only in Tulsa County)
Holdenville Formation or Holdenville Shale (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- "Holdenville Shale"- Mainly clay shale with some interbedded fine-grained calcareous sandstone locally containing beds of crystalline limestone. Thickness ranges from 100 to 280 feet. FORT SMITH- "Holdenville Shale"- Shale, thin sandstone and minor limestones. ARDMORE-SHERMAN- "Holdenville Formation"- Shale, blue-gray, with light-brown sandstones and chert conglomerates and 2 prominent limestones--the upper, or "Sasakwa Limestone," white, fine-grained, 1 to 15 feet thick, 35 feet below the top, and the lower, or "Homer Limestone," dark-brown, sandy, 2 to 10 feet thick, 40 to 70 feet below the Sasakwa. Thickness, 210 to 260 feet. (Upper Franks Conglomerate)
Hoxbar Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ARDMORE-SHERMAN- Upper most member of Glenn Fm, consisting of brown limestone, white sandstone, and shale. "Zuckerman Sandstone" (top eroded) down to base of "Confederate Limestone;" thickness, 2,800 feet. Occurs in the ARDMORE BASIN
Hunton Group (Phanerozoic | Paleozoic | Silurian Devonian-Early)
ARDMORE-SHERMAN- Marlstone, shale, and limestone, buff, ranging in age from Early Silurian to Early Devonian; thickness, 100 to 700 feet, with many unconformities Occurs in the ARBUCKLE MTNS
Jackfork Group or Jackfork Sandstone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
ARDMORE-SHERMAN- "Jackfork Sandstone"- Sandstone, gray, white, and tan, coarse-grained, cherty, with gray shale and some boulders up to 7 feet in diameter; thickness 1,150 to 5,000 feet Occurs in the OUACHITA MNTS McALESTER TEXARKANA- "Jackfork Group"- Sandstone, tan to gray, fine- to coarse-grained, quartzose, with some mica, poorly to well-indurated, quartzitic has some gray shale and several maroon shales; black, white-speckled "Chickasaw Creek Chert" is at base; thickness, 1,500 to 6,000 feet or more. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT
Johns Valley Formation or Johns Valley Shale (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
ARDMORE-SHERMAN- "Johns Valley Formation"- Shale, dark-gray, with boulder conglomerate; thickness, 425 to 900 feet. Occurs in the OUACHITA MNTS McALESTER TEXARKANA- "Johns Valley Shale"- Shale, dark-gray, with some stringers of Wapanucka-like limestone in northwestern part of area; contains exotic boulders of southern Arbuckle Mountain facies, ranging from Fort Sill to Goddard and as large as 369 feet in diameter; some Wapanucka nodules are not exotic but were formed in place; thickness, 300 to 1,000 feet. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT.
Keokuk and Reeds Spring Formations and St. Joe Group (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early)
TULSA- "Keokuk Formation," chert and limestone. "Reeds Spring Formation," chert and limestone. "St. Joe Group," limestone and shale. FORT SMITH- Mkr "Keokuk Formation," chert; "Reeds Spring Formation," chert and limestone; and "St. Joe 'Group,'" limestone and marlstone.
Kiamichi Formation (Phanerozoic | Mesozoic | Cretaceous-Early )
ARDMORE-SHERMAN- Shale, dark-gray, plastic, with oyster-shell limestones; thickness, about 30 feet. McALESTER TEXARKANA- Shale, dark-gray to black, with some brown fossiliferous limestones, with "Texigryphaea navia;" thickness, 28 to 36 feet, and up to 80 feet in subsurface of southern McCurtain County.Ouachita Mountain uplift; S. OK folded belt province
Kindblade Formation (Phanerozoic | Paleozoic | Ordovician-Early)
ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained, gradational eastward into tan fine- to coarse-grained dolomite; some tan to gray sandstone and shale; thickness, 1,875 to 3,000 feet, decreasing eastward. (Arbuckle Group) Individual Fm description not found. Occurs in the ARBUCKLE MTNS
Kingman Formation or Kingman Siltstone (Phanerozoic | Paleozoic | Permian )
WOODWARD- "Kingman Formation"- Orange-brown to greenish-gray fine-grained sandstone and siltstone, with some red-brown shale. Thickness is about 70 feet. ENID- "Kingman Siltstone"- Mainly red-brown with several thin layers of greenish-gray and orange-brown calcitic siltstone. Thickness, about 70 feet (20 m). (Hennessey Group) OKLAHOMA CITY- "Kingman Siltstone"- Orange-brown to greenish- gray, even bedded siltstones with some fine-grain sandstone and red-brown shale; grades southward into "Purcell Sandstone". Thickness, 30 feet. (Hennessey Group)
Kiowa Formation (Phanerozoic | Mesozoic | Cretaceous-Early )
WOODWARD- Gray and yellow shale and limestone, with many "Texigryphaea" shells locally. At base is 5 to 10 feet of greenish-gray sandstone in places. Thickness ranges up to 140 feet with top eroded. CLINTON- Outliers of the "Kiowa Formation," Kk, dark-gray shale with some thin beds of fossiliferous tan limestone, range in thickness from a few feet to about 20 feet. Associated in some places is a 5- to 10-foot, gray to brown, coarse-grained sandstone and conglomerate assigned to the overlying "Dakota Group," Kd, (lower sandstone part).
Labette Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Shale and thin sandstone and limestone.
Lenapah Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Limestone and shale. (Map unit only in Nowata County)
Lewisville Member of Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late )
ARDMORE-SHERMAN- mostly shale and weakly indurated sandstone, about 75 feet thick.
Limestone Gap (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
McALESTER TEXARKANA- Shale and sandstone, gray to tan, illitic, chloritic, micaceous, quartzose, fine- to coarse-grained, moderately to well-indurated, with some ironstone concretions and many bottom marks; thickness, approximately 1,000 feet, pinching out in subsurface near Ti Valley Fault. Fault. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.
Lower part of Arbuckle Group and Timbered Hills Group (Phanerozoic | Paleozoic | Cambrian-Furongian)
LAWTON- Limestone, dolomite, siltstone, sandstone, conglomerate, and shale, with glauconitic and hematitic zones; thickness, 1,200 to 2,000 feet (370 to 600 m), faulted in isolated areas. Lower part of "Arbuckle Group" includes "Signal Mountain Formation, Royer Dolomite," and "Fort Sill Limestone; Timbered Hills Group" includes "Honey Creek Formation" and "Reagan Sandstone."
Lynn Mountain Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
McALESTER TEXARKANA- Shale, gray to tan, with many fine- to coarse-grained, quartzose, micaceous sandstone with many bottom markings; top eroded; thickness, 3,000 to 7,000 feet or more; unconformable upon Goddard, Delaware Creek, Woodford, and older beds that are exposed north and west of Ti Valley Fault. Occurs in the OUACHITA MTNS
Marlow Formation (Phanerozoic | Paleozoic | Permian )
WOODWARD- Orange-brown fine-grained sandstone and siltstone, with some interbedded red-brown shale and silty shale in upper part and some thin gypsum beds at base, about 35 feet above base, and at top. The upper two gypsum and (or) dolomite beds are generally pink to maroon and less than 1 foot thick; they may erode into mappable escarpments about 20 feet apart, being named "Emanuel Bed" at top (mapped) and "Relay Creek Bed" 15 to 20 feet below the top (not mapped). In places the basal Marlow is a greenish-gray medium-grained sandstone. In Woods and Woodward Counties, the "Doe Creek Lentil" (Pmd) is a coarse-grained calcareous sandstone with algal clumps and invertebrate fossils, ranging up to 70 feet thick from the base of the Marlow to the Relay Creek Bed, cropping out in a narrow band of high hills striking northeast. Thickness is about 120 feet, with top eroded at many places. CLINTON- "Marlow Formation," Pm, orange-brown, fine-grained sandstone and siltstone, about 100 to 130 feet thick, thinning northward. This formation has 2 gypsum and (or) dolomite beds in upper 20 feet--the "Emanuel Bed" (at top) and the "Relay Creek Bed" (20 feet below top). Two thin, pale shales occur; the first is 1 foot below the top ("Gracemont") and the second is 55 feet above the base (unnamed). OKLAHOMA CITY- Mostly orange-brown fine-grained gypsiferous sandstone, with some red-brown shale. Contains 10 feet of calcitic sandstone lenses near middle and 2 thin dolomites (or gypsums) at top. Exposed thickness, about 50 feet (top 50 to 75 feet eroded). (Whitehorse Group) LAWTON- "Marlow Formation," Pm, very fine-grained sandstone with some silty shale; thickness, about 90 to 130 feet (27 to 40 m); contains 2 thin gypsum and (or) dolomite beds in upper 20 feet (6 m)-the "Emanuel Bed" (at top) and the "Relay Creek Bed" (20 feet below top). (Whitehorse Group) ARDMORE-SHERMAN- Sandstone, orange-brown, fine- to medium-grained, moderately indurated, with "Verden Sandstone Lentil," Pmv, 10 feet thick near middle, and "Relay Creek" and "Emanuel" dolomite and gypsum beds at top; thickness, 105 to 135 feet. (Whitehorse Group)
Mazarn Shale (Phanerozoic | Paleozoic | Ordovician-Early)
McALESTER TEXARKANA- Shale and phyllite, dark-gray to black, micaceous; estimated thickness, 1,000 feet, with maximum thickness in Arkansas 3,000 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
McAlester and Hartshorne Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- "McAlester and Hartshorne Formations", shale and some sandstone and coal. FORT SMITH- IPmh "McAlester" and "Hartshorne Formations" (undifferentiated), shale, sandstone, and coal.
McAlester Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ARDMORE-SHERMAN- Shale, gray, with "Upper Hartshorne coal" 1 to 50 feet above base, 500 to 600 feet thick; overlain by dark-gray shale with many buff fine-grained sandstones, 595 to 1,030 feet thick; overlain by dark-gray shale, 300 to 925 feet thick, with "McAlester coal," 1 to 3 feet thick, a few feet above base. Total thickness ranges from 1,150 to 2,420 feet. (Lower Franks Conglomerate) McALESTER TEXARKANA- Shale, gray, illitic, chloritic, with many tan to gray sandstones, fine- to coarse-grained, micaceous, quartzose; "McAlester and Stigler coals" 600 to 800 feet or more below top; thickness, 2,000 to 2,830 feet, increasing eastward
Mesozoic rocks undifferentiated (Phanerozoic | Mesozoic | Triassic-Early Triassic-Middle(?) Triassic-Late(?) Jurassic(?) Cretaceous-Early(?) Cretaceous-Middle(?) Cretaceous-Late)
TEXAS- Red shale containing thin layers of yellow and gray clay and indistinctly bedded fine-grained buff, red, white, and gray sandstone. May include beds of Cretaceous, Jurassic, and Triassic ages. Their exposed thickness is less than 100 feet.
Mississippian Rocks above Chattanooga Shale Undifferentiated (Phanerozoic | Paleozoic | Carboniferous Mississippian)
FORT SMITH- Mu- Undifferentiated Mississippian Rocks above Chattanooga Shale. Includes: Pitkin, Fayetteville, Hindsville, Moorefield, Keokuk and Reeds Spring Formations, and St. Joe Group.
Missouri Mountain and Polk Creek Shales (Phanerozoic | Paleozoic | Ordovician-Late Silurian)
McALESTER TEXARKANA- Shale, greenish-gray to maroon to black; grades into phyllite in Broken Bow Uplift; contains some thin sandstones and gray conglomerates; a fossiliferous limestone occurs in Southeast quarter section 29, Township 4 South, Range 23 East; mapped as SmOp in Potato Hills, where it is included with Polk Creek Shale; thickness, 60 to 110 feet or less. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
Missouri Mountain Shale (Phanerozoic | Paleozoic | Silurian)
McALESTER TEXARKANA- Shale, greenish-gray to maroon to black; grades into phyllite in Broken Bow Uplift; contains some thin sandstones and gray conglomerates; a fossiliferous limestone occurs in Southeast quarter section 29, Township 4 South, Range 23 East; mapped as SmOp in Potato Hills, where it is included with Polk Creek Shale; thickness, 60 to 110 feet or less. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
Missouri Mountain Shale and Blaylock Sandstone (Phanerozoic | Paleozoic | Silurian)
ARDMORE-SHERMAN- "Missouri Mountain Shale," shale, black to gray-green to red; thickness, 100 feet; underlain by sandstone, several feet thick, correlated as "Blaylock." Occurs in the OUACHITA MNTS
Morrison Formation (Phanerozoic | Mesozoic | Jurassic-Late )
CIMARRON- Varicolored fine-grained sandstone, limestone, dolomite, shale, and conglomerate 0 to 470 +/- feet thick.
Morrowan-Atokan (?) rocks undifferentiated (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early Pennsylvanian-Middle)
ARDMORE-SHERMAN- Shale and sandstone, gray to brown, fine- to coarse-grained; thickness, 5,000 to 9,000 feet. Occurs in the OUACHITA MNTS
Morrowan rocks undifferentiated (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
ARDMORE-SHERMAN- Shale and sandstone, gray to brown, fine- to coarse- grained;estimated thickness, 3,000 feet Occurs in the OUACHITA MNTS.
Nellie Bly Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Shale and thin sandstone. ARDMORE-SHERMAN- Shale, siltstone, fine-grained sandstone, chert conglomerate, limestone, and limestone conglomerate, dark-gray to buff; thickness, 200 to 300 feet.
Nellie Bly Formation and Hogshooter Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- "Nellie Bly Formation" consists mainly of shale with a few layers of fine- to medium-grained sandstone. Thickness ranges from 80 to 550 feet (25 to 170 m). Underlying "Hogshooter Limestone" is massive crinoidal limestone 1 to 50 feet (0.3 to 14 m) thick. OKLAHOMA CITY- "Nellie Bly Formation," mainly shale with many fine-grained sandstone beds and limestone beds locally in upper part; thickness, about 250 to about 550 feet. Underlying"Hogshooter Limestone," massive crinoidal limestone 1 to 15 feet thick.
Nowata Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Shale and minor sandstone and limestone.
Oil Creek and Joins Formation (Phanerozoic | Paleozoic | Ordovician-Middle)
ARDMORE-SHERMAN- Limestone, gray to tan, granular, with greenish-gray shale and brown fine- to medium-grained sandstone; thickness, 600 to 1,100 feet, decreasing eastward. (Simpson Group) Occurs in the ARBUCKLE MTNS
Oolagah Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Thin-bedded limestone and some shale in the southern part of the area. North of Oolagah, in western Rogers County, the map unit, IPol, includes the following formations: "Altamont Formation," limestone and minor shale; "Bandera Formation," shale and thin sandstone; "Pawnee Formation," limestone and minor shale.
Oscar Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late)
ENID- Mainly shale with many layers of limestones that pinch out southward, where fine-grained arkosic sandstones are thicker and more numerous. Near Kansas border, sequence is (descending): "Herington Limestone" (20 feet thick) at top, "Enterprise Shale" (45 feet thick), "Winfield Limestone, "IPowi (8 feet thick), "Gage Shale" (80 feet thick), "Towanda Limestone" (3 feet thick), "Holmesville Shale" (25 feet thick), "Fort Riley Limestone," IPofr (30 feet thick) and underlying Florence Flint, IPofr (8 feet thick), "Blue Springs Shale" (60 feet thick), "Kinney Limestone" (5 feet thick), "Wymore Shale" (22 feet thick), "Wreford Limestone," IPowr (25 feet thick), "Speiser Shale" (38 feet thick), "Funston Limestone (4 feet thick), "Blue Rapids Shale" (15 feet thick), "Crouse Limestone" (6 feet thick), "Easly Creek Shale" (12 feet thick), "Bader Limestone" (5 feet thick), "Stearns Shale" (10 feet thick), "Morrill Limestone" (2 feet thick), "Florena Shale" (6 feet thick), "Cottonwood Limestone," IPoc (3 feet thick), "Eskridge Shale" (6 feet thick), and "Neva Limestone" (25 feet thick) at base. Total thickness, about 400 feet. OKLAHOMA CITY- Red-brown to gray shale and orange-brown fine-grained, crossbedded sandstone; grades southward into arkosic sandstone and conglomerate. Includes "Herington Limestone" at top inPayne County, "Neva Limestone" (0.2 to 1.2 feet thick) at basein Lincoln County, and "Hart Limestone" (4 to 10 feet thick)at base in Pottawatomie County. In Payne County, includesthin stringers of "Winfield Limestone," IPowi (75 feet belowtop), "Fort Riley Limestone," IPofr (245 feet below top),"Wreford Limestone," IPowr (345 feet below top), and"Cottonwood Limestone," IPoc (525 feet below top). Thickness ranges from 300 feet in south to 600 feet in north. LAWTON- Shale, sandstone, and arkose, 300 to 500 feet (90 to 150 m) thick, base covered. ARDMORE-SHERMAN- Shale, red-brown to gray, with arkosic sandstones and limestone conglomerates near Arbuckle Mountains; "Hart Limestone" at base; thickness, 300 to 500 feet, decreasing southeastward. (Pontotoc Group)
Permian rocks undifferentiated (Phanerozoic | Paleozoic | Permian)
TEXAS- Red to dark reddish-brown shale, sandstone, and siltstone. Gypsum occurs in all rock units as a cementing agent, as tiny flakes, as thin irregular veinlets, and as discontinuous beds ranging from less than an inch to more than 30 feet thick. Maximum thickness exceeds 2,000 feet. BEAVER- Red shale, sandstone, and siltstone, are predominant rocks with lesser amounts of limestone, dolomite, gypsum, and salt. The undifferentiated Permian rocks include the Whitehorse Group, the Cloud Chief Formation, and the Quartermaster Formation; also included are local outcrops in the southwestern part of the county, which maybe Triassic in age, 3,800 feet thick
Pitkin + Fayetteville + Batesville + Hindsville + Moorefield Formations (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late)
TULSA- "Pitkin Formation," limestone. "Fayetteville Formation," shale and thin limestone "Batesville Formation," fine-grained sandstone "Hindsville Formation," limestone and shale "Moorefield Formation," limestone, shale, and siltstone.
Pitkin + Fayetteville + Hindsville + Moorefield Formations (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late)
FORT SMITH- Mp "Pitkin Formation," limestone; "Fayetteville Formation," shale and limestone; "Hindsville Formation," limestone and shale; and "Moorefield Formation," limestone.
Polk Creek Shale (Phanerozoic | Paleozoic | Ordovician-Late)
ARDMORE-SHERMAN- Shale, black; thickness, 175 feet. Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- Shale and phyllite, dark-gray to black, with some chert nodules; contains many graptolites; thickness, 75 to 140 feet. (Same as Sylvan Shale in Arbuckle Mountains.) Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
Post Oak Conglomerate (Phanerozoic | Paleozoic | Permian )
LAWTON- "Post Oak Conglomerate," Ppo, limestone conglomerate near limestone outcrops; contains zeolite-opal ("Tepee Creek Formation") locally, near gabbro and anorthosite outcrops; arkosic gravel and cobbles near igneous outcrops. These rock types are interbedded with sand, silt, clay, and shale, as much as 500 feet (150 m) thick at surface but several thousand feet thick in subsurface, extending down section into Pennsylvanian rocks.
Purcell Sandstone (Phanerozoic | Paleozoic | Permian )
OKLAHOMA CITY- Red-brown to maroon fine- to coarse-grained sandstone, mudstone conglomerate, and red- brown shale. Thickness, 150 feet. (Hennessey Group) ARDMORE-SHERMAN- Sandstone, red-brown to maroon and greenish-gray, fine- to coarse-grained, with some shale and mudstone conglomerate; thickness, 90 to 150 feet, decreasing southward. (Hennessey Group).
Purgatoire Formation (Phanerozoic | Mesozoic | Cretaceous-Early )
CIMARRON- Kiowa Shale Member: Gray to black fossiliferous shale with sandstone in the upper part. Thickness ranges from 0 to 50 +/- feet. Cheyenne Sandstone Member: Massive, white to buff, fine- to medium-grained sandstone, containing some conglomerate in the lower part, from 0 to 120 +/- feet thick.
Red Branch Member of Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late )
ARDMORE-SHERMAN- indurated sandstone, shale, and lignite, about 75 feet thick, erodes to an escarpment; and basal Dexter Member.
Rush Springs Formation (Phanerozoic | Paleozoic | Permian )
WOODWARD- Orange-brown fine-grained sandstone, commonly crossbedded, with some interbedded red-brown shale, silty shale, and gypsum beds. In southern part of area, about 30 feet below top is a thin massive gypsum bed ("Weatherford Bed" or "One Horse Bed"), not mapped here. About 100 feet lower is another thin gypsum bed ("Old Crow Bed") not mapped here. Thickness is about 190 feet in southern part and 90 feet near Kansas border, with top eroded in many places. CLINTON- "Rush Springs Formation," Pr, orange-brown, cross-bedded, fine-grained sandstone with some dolomite and gypsum beds. Thickness, about 300 feet, thinning northward to about 186 feet. LAWTON- "Rush Springs Formation," Pr, very fine-grained, cross-bedded sandstone, 136 to 300 feet (41 to 90 m) thick. The "Weatherford Gypsum Bed," Prw, contains gypsum and dolomite and is as much as 60 feet (18 m) thick in the upper part of the Rush Springs. (Whitehorse Group) ARDMORE-SHERMAN- Sandstone, orange-brown, fine- to medium-grained, moderately indurated, with "Weatherford Gypsum Bed," Prw, 2 to 15 feet thick, near top. Thickness, about 280 feet, top eroded (Whitehorse Group)
Salt Plains Formation (Phanerozoic | Paleozoic | Permian )
WOODWARD- Orange-brown fine-grained sandstone and siltstone, with a greenish-gray sandstone in middle 30 feet ("Crisfield Sandstone Member") unmapped. Thickness ranges up to 160 feet. ENID- Mainly red-brown shale with several thin beds of orange-brown, fine-grained sandstone. Thickness about 160 feet (50 m). (Hennessey Group) OKLAHOMA CITY- Red-brown blocky shale orange-brown siltstone, grades southward into Pp "Purcell Sandstone" in Norman area. Thickness, 200 feet. (Hennessey Group)
San Angelo Sandstone (Phanerozoic | Paleozoic | Permian )
LAWTON- "San Angelo Sandstone," Psa, interstratified sandstone, mudstone conglomerate, and shale, as much as 80 feet (24 m) thick.
Savanna and McAlester Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
FORT SMITH- IPsm "Savanna" and "McAlester Formations" (undifferentiated; T. 15 N., Rs. 18, 19 E.), shale and minor sandstones
Savanna Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- "Savanna Formation," shale and thin sandstone, limestone, and coal. FORT SMITH- IPsa "Savanna Formation," shale, sandstone, and coal ARDMORE-SHERMAN- Sandstone and shale, gray to brown, fine- to coarse- grained, cherty, with several thin coal seams near middle; thickness, 1,120 to 1,600 feet (Lower Franks Conglomerate) McALESTER TEXARKANA- Shale, tan to brown, illitic, chloritic, and sandstone, fine-to coarse-grained, micaceous, quartzose, with several thin coal seams in middle, one of which is "Cavanal coal;" thickness, 1,470 to 2,000 feet, increasing eastward.
Savanna + McAlester + Hartshorne + Atoka Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- "Savanna, McAlester, Hartshorne, and Atoka Formations," shale, sandstone, siltstone, limestone, and coal.
Savanna + McAlester + Hartshorne Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- "Savanna, McAlester, and Hartshorne Formations," shale and some sandstone, limestone, and coal
Seminole Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Shale, sandstone, and thin coal beds. OKLAHOMA CITY- Chert conglomerate, shale, and fine-grained sandstone containing coal seams in upper part locally. Thickness ranges from 100 to 375 feet. FORT SMITH- Sandy shale, sandstone, and thin coal seams. ARDMORE-SHERMAN- Shale, gray-green, with buff fine-grained sandstones, chert conglomerates, and limy sandstones; thickness, about 120 feet. (Upper Franks Conglomerate)
Senora Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Shale with thin and lenticular sandstone, minor limestone, and coal. OKLAHOMA CITY- Mainly fine-grained micaceous sandstone and shale locally containing coal beds. Thickness ranges from about 500 to 950 feet. FORT SMITH- Shale, sandstone, and thin coal seams. ARDMORE-SHERMAN- Shale, gray, and light-brown medium-grained sandstone; thickness, 150 to 500 feet, decreasing southwestward. Subdivided into lower sandstone, 350 feet thick, and upper shale, 150 feet thick.
Stanley Group or Stanley Shale (Phanerozoic | Paleozoic | Carboniferous Mississippian)
ARDMORE-SHERMAN- "Stanley Shale"- Shale, dark-gray, siliceous,with some gray to buff fine-grained sandstones; thickness,10,000 feet Occurs in the OUACHITA MNTS McALESTER TEXARKANA- "Stanley Group"- Shale, olive-green to gray, illitic, chloritic, with many5- to 30-foot-thick beds of poorly sorted, micaceous, quartzose sandstones and some thin siliceous cherty beds and black shales; several tuff beds occur in basal 1,000 feet and are indicated by red line in Stanley exposures as designated on map; many asphaltite, lead, and quartz veins occur along fault zones; mostly Chesterian age; thickness, 7,500 to 14,000 feet or more. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT
Stuart Shale (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- Mostly laminated clay shale and minor amounts of silty sandstone. Thickness ranges from 80 to 180 feet. FORT SMITH- Shale and minor sandstone. ARDMORE-SHERMAN- Shale, blue to dark-gray, with some fine- to medium-grained brown sandstones; thickness, 80 to 300 feet, decreasing southwestward. McALESTER TEXARKANA- Shale, blue to dark-gray, with some fine- to medium-grained sandstones; top eroded; lower 20 feet exposed.
Sylvan Shale + Fernvale Limestone and Viola Limestone (Phanerozoic | Paleozoic | Ordovician-Middle Ordovician-Late)
ARDMORE-SHERMAN- "Sylvan," shale, dark-greenish-gray; thickness, 60 to 325 feet. "Fernvale" and "Viola," limestone, gray, fine- to coarse-grained; thickness, 350 to 900 feet. Occurs in the ARBUCKLE MTNS
Tallant Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- Alternating layers of shale and fine- to medium-grained sandstone. Thickness ranges from 75 to 250 feet (23 to 75 m). OKLAHOMA CITY- Mostly fine- to medium-grained sandstone 10 to 60 feet thick overlain by shale 25 to 65 feet thick. Cut out by "Vamoosa Formation" in central part of area. Total thickness ranges from 0 to 100 feet.
Templeton Member of Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late )
ARDMORE-SHERMAN- indurated sandstone and shale, about 75 feet thick, erodes to an escarpment; (Woodbine Formation)
Thurman Sandstone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- Mainly medium-grained, silty sandstone with cherty conglomerate at base. Only a few feet exposed in quadrangle. FORT SMITH- Sandstone and shale. ARDMORE-SHERMAN- Sandstone, brown, fine- to coarse-grained, with some gray shale and basal 50-foot chert conglomerate; thickness, 80 to 250 feet, decreasing southwestward. McALESTER TEXARKANA- Sandstone, brown, fine- to coarse-grained, with some gray shale and a basal 50-foot chert conglomerate; grades northward into Boggy Formation; top eroded at many places; thickness, 200 feet.
Tokio Formation (Phanerozoic | Mesozoic | Cretaceous-Late )
McALESTER TEXARKANA- Sand, light-gray, fine- to coarse-grained, quartzose, poorly sorted, crossbedded, and gray clay shale, with many cylindrical pipe structures, petrified wood and invertebrates; same as Bonham Marl and Austin Chalk of Texas; thickness ranges from 88 to 380 feet, increasing eastward; reaches thickness of 595 feet in subsurface southeastward.
Torpedo Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- Thin-bedded to massive medium-grained sandstone and shale
Undifferentiated, Mississisippian, Devonian, Silurian, and Ordovician (Phanerozoic | Paleozoic | Ordovician-Early Ordovician-Middle(?) Ordovician-Late(?) Silurian(?) Devonian(?) Carboniferous Mississippian-Early(?) Mississippian-Middle(?) Mississippian-Late)
FORT SMITH- Mississisippian, Devonian, Silurian, and Ordovician Rocks, Undifferentiated Mississippian and Devonian. "Chattanooga Shale," shale. Devonian. "Sallisaw Formation," limestone, sandstone, and chert; and "Frisco Formation," limestone. Silurian. "Quarry Mountain Formation," limestone; "Tenkiller Formation," limestone; and "Blackgum Formation," limestone and dolomite. Ordovician. "Sylvan Shale," shale; "Fernvale Limestone," limestone; "Fite Limestone," limestone; "Tyner Formation," shale, sandstone, dolomite, and limestone; "Burgen Sandstone," sandstone and minor shales and limestones; and "Cotter Dolomite," dolomite.
Upper Holdenville Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- Mainly shale with interbedded fine-grained sandstone locally containing beds of limestone. Only a few feet is exposed in quadrangle
Vamoosa Group or Vamoosa Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late)
ENID- "Vamoosa Group"- Alternating layers of shale and fine- to coarse-grained sandstone, with some thin limestones. Sandstone layers are thicker, coarser grained, and more numerous southward. Group near Kansas border includes (descending): unnamed shale and sandstone (160 feet thick) at top, "Plattsmouth Limestone, "IPvap (14 to 23 feet thick), unnamed shale and sandstone (15 to 90 feet thick), "Leavenworth Limestone," IPvale (4 feet thick), unnamed shale and sandstone (170 feet thick) "Labadie Limestone," IPval (6 to 23 feet thick; may also be called "Haskell Limestone"), unnamed shale and sandstone (60 to 100 feet thick), "Bowring Limestone," IPvab (2 feet thick; may also be called "Westphalia Limestone"), unnamed shale (5 to 10 feet thick), and basal "Cheshewalla Sandstone (7 to 20 feet thick; also called "Tonganoxie Sandstone"). Total thickness about 630 feet (190 m) OKLAHOMA CITY- "Vamoosa Formation"- Alternating thin to massive layers of fine- to coarse-grained sandstone and sandy, silty shale containing some chert conglomerate in middle and lower parts of formation. Thickness ranges about 200 to about 690 feet. ARDMORE-SHERMAN- "Vamoosa Formation"- Shale, sandstone, and chert conglomerate; red-brown to buff fine- to coarse-grained sandstone. Subdivided into 12 members, each with coarse clastics at base overlain by shale. Thickness, about 125 to 260 feet (to 1,000 feet in subsurface), decreasing southward.
Vamoosa + Tallant + Barnsdall Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- "Vamoosa Formation," shale, sandstone, siltstone, and thin limestone. "Tallant Formation," shale, sandstone, and thin limestone. "Barnsdall Formation," shale, siltstone, sandstone, and thin limestone
Vanoss Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late)
ENID- Alternating layers of limestone and shale to north, grading southward into limestone, shale, and fine-grained arkosic sandstone. Locally group contains thin coal seams. Near Kansas border, group includes (descending): "Salem Point Shale" (12 feet thick) at top, underlain by "Burr Limestone" (8 feet thick), "Legion Shale" (4 feet thick), "Sallyards Limestone" (3 feet thick), "Roca Shale" (15 feet thick), "Red Eagle Limestone," IPvre (20 feet thick), "Johnson Shale" (35 feet thick), "Long Creek Limestone," IPvlc (10 feet thick), unnamed shale (3 feet thick), "Hughes Creek Limestone (15 feet thick), unnamed shale (12 feet thick), "Americus Limestone, "IPvam, (12 feet thick), "Oaks Shale" (3 feet thick), "Houchen Creek Limestone (8 feet thick), "Stine Shale" (20 feet thick), "Five Point Limestone" (3 feet thick), unnamed shale (12 feet thick), "Brownville Limestone, IPvb (8 feet thick), "Pony Creek Shale" (40 feet thick), "Grayhorse Limestone," IPvg (5 feet thick), unnamed shale (12 feet thick), "Nebraska City Limestone" (5 feet thick), "French Creek Shale" (12 feet thick), "Jim Creek Limestone" (3 feet thick), "Friedrich Shale" (30 feet thick), "Grandhaven Limestone" (2 feet thick), "Dry Shale" (25 feet thick), "Dover Limestone" (30 feet thick), "Willard-Langdon Shale" (110 feet thick), "Elmont Limestone," IPve (10 feet thick), "Stonebreaker Shale" (20 feet thick), and "Reading Limestone" (20 feet thick) at base. Total thickness, about 500 feet (150 m). OKLAHOMA CITY- Red-brown to gray shale and orange-brown fine-grained, crossbedded sandstone; grades southward into arkosic sandstoneand conglomerate. Includes many thin limestone beds and shale units north of North Canadian River (descending): "Roca Shale"(75 feet thick), "Red Eagle Limestone," IPvre (3 to 8 feetthick), "Johnson Shale" (60 feet thick), "Long Creek Limestone," IPvlc (9 to 12 feet thick), "Hughes Creek Shale" (52 feet thick), "Americus Limestone," IPva (1.0 to 2.5 feetthick), "Admire Shale" (70 feet thick), "BrownvilleLimestone," IPvb (1 to 3 feet thick), "Pony Creek Shale" (75 feet thick), "Grayhorse Limestone," IPvg (1 foot thick), unnamed shale (70 feet thick), "Elmont Limestone," IPve (1.2to 7.8 feet thick), "Stonebreaker Shale" (60 feet thick), and"Reading Limestone" (1.5 feet thick), at base. Totalthickness of group ranges from 250 feet in south to 490 feet in north. ARDMORE-SHERMAN- Shale, maroon, arkose, and limestone conglomerate; thickness, 250 to 900 feet (subsurface), decreasing southward. (Pontotoc Group)
Van Vacter Member of Blaine Formation (Phanerozoic | Paleozoic | Permian )
LAWTON- "Van Vacter Member," Pbv, of the Blaine Formation contains 6 dolomite-gypsum-shale sequences with a total thickness of 80 to 105 feet (24 to 32 m).
Viola Limestone and Bromide Formation (Phanerozoic | Paleozoic | Ordovician-Late)
CLINTON- Limestone, limestone and shale interbedded, and sandstone; thickness, about 900 feet; one outlier is shown in southern part of quadrangle. Simpson and lower units are covered. LAWTON- Limestone, interbedded limestone and shale, and sandstone; thickness about 900 feet (270 m), faulted in isolated areas, top eroded, base covered.
Wann and Iola Formations or Iola Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
ENID- "Wann Formation" consists of shale and fine- to medium-grained sandstone with many thin layers of fossiliferous limestone. Thickness ranges from 50 to 400 feet (15 to 122 m). "Iola Limestone" is mainly limestone, calcareous sandstone, and shale and underlies Wann. Thickness ranges 4 to 100 feet (1 to 30 m). TULSA- "Wann Formation," shale with thin sandstone and limestone. "Iola Formation," limestone and shale. OKLAHOMA CITY- "Wann Formation," shale and fine- to medium-grained sandstone; thickness, 40 to 180 feet. Underlying "Iola Limestone," mainly fine-grained calcareous sandstone and limestone with some shale; thickness, 15 to 20 feet.
Wapanucka Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained to oolitic. Mapped separately along Lawrence uplift as IPwal, 30 to 75 feet thick with gray shale, IPwas, below, about 160 feet thick. Occurs in the ARBUCKLE MTNS
Wapanucka Formation and Chickachoc Chert (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
ARDMORE-SHERMAN- Limestone, gray to brown, spicular, granular to oolitic; alternates with gray shale and calcareous sandstone; thickness, 270 to 720 feet. Chert content increases southeastward. Occurs in the OUACHITA MTNS McALESTER TEXARKANA- Limestone, gray to brown, oolitic to granular, with sponge-spicular chert in middle 50 to 114 feet with overlying and underlying calcareous sandstones and shales; thickness, 600 to 700 feet, pinching out in subsurface near Ti Valley Fault. Occurs in the OUACHITA MTNS, NORTH OF TI VALLEY FAULT.
Wellington Formation (Phanerozoic | Paleozoic | Permian )
ENID- Mostly red-brown shale to north, grading into fine-grained sandstone and mudstone conglomerate southward into Logan County. Thickness, about 850 feet (260 m). (Sumner Group) OKLAHOMA CITY- Red-brown shale and orange-brown fine-grained sandstone, containing much maroon mudstone conglomerate and chert conglomerate to south. Thickness ranges from about 150 feet in south to 500 feet in north. (Sumner Group) LAWTON- Maroon shale, about 130 feet (40 m) thick, with greenish-gray and black sandstone of the "Ryan Sandstone Bed" at base. (Sumner Group) ARDMORE-SHERMAN- Shale, red-brown, with several 20- to 30-foot bituminous sandstones at base ("Ryan"); thickness, about 100 to 200 feet, decreasing southeastward.
West Spring Creek and Kindblade Formations (Phanerozoic | Paleozoic | Ordovician-Early)
LAWTON- "West Spring Creek Formation" and "Kindblade Formation," Owk, dolomite, dolomitic sandstone, conglomerate, and limestone; thickness, approximately 2,000 feet (600 m). (Upper part of Arbuckle Group). ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained, gradational eastward into tan fine- to coarse-grained dolomite; some tan to gray sandstone and shale; thickness, 1,875 to 3,000 feet, decreasing eastward. (Arbuckle Group) Individual Fm description not found. Occurs in the ARBUCKLE MTNS
West Spring Creek Formation (Phanerozoic | Paleozoic | Ordovician-Early)
ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained, gradational eastward into tan fine- to coarse-grained dolomite; some tan to gray sandstone and shale; thickness, 1,875 to 3,000 feet, decreasing eastward. (Arbuckle Group) Individual Fm description not found Occurs in the ARBUCKLE MTNS
Wetumka Shale (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- Mainly sandy, silty, laminated shale 100 to 200 feet thick FORT SMITH- Shale, minor sandstones, and minor limestones. ARDMORE-SHERMAN- Shale, blue-gray, with some sandstones and siltstones; thickness, 120 to 250 feet
Wewoka Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
OKLAHOMA CITY- Interbedded fine- to medium-grained sandstone and calcareous shale. Thickness ranges from 400 to 750 feet. FORT SMITH- Shale, sandstone, and minor limestones ARDMORE-SHERMAN- Shale, blue-gray, sandstone, chert conglomerate, and limestone conglomerate; thickness, 400 feet.
Whitehorse Group (Phanerozoic | Paleozoic | Permian )
CLINTON- Predominantly orange-brown, fine-grained sandstone, the "Whitehorse Group" is mapped as Pwh where separate formations have not been distinguished and as the "Rush Springs Formation" and the "Marlow Formation" where identified. "Rush Springs Formation," Pr, orange-brown, cross-bedded, fine-grained sandstone with some dolomite and gypsum beds. Thickness, about 300 feet, thinning northward to about 186 feet. The "Weatherford Gypsum Bed," Prw, is about 30 to 60 feet below the top (mapped in southeastern part only). "Marlow Formation," Pm, orange-brown, fine-grained sandstone and siltstone, about 100 to 130 feet thick, thinning northward. This formation has 2 gypsum and (or) dolomite beds in upper 20 feet--the "Emanuel Bed" (at top) and the "Relay Creek Bed" (20 feet below top). Two thin, pale shales occur; the first is 1 foot below the top ("Gracemont") and the second is 55 feet above the base (unnamed). The "Verden Sandstone Lentil," Pmv, is a coarse-grained, calcareous, fossiliferous sandstone (2 to 10 feet thick) that occurs in the middle of the Marlow, about 25 feet below the Relay Creek Bed and 85 to 95 feet above the base. LAWTON- Predominantly orange-brown, fine-grained sandstone, the "Whitehorse Group" is mapped as Pwh where separate formations have not been distinguished and as the "Rush Springs Formation" and the "Marlow Formation" where identified. "Whitehorse Group undifferentiated," Pwh, fine-grained sandstone and siltstone as much as 100 feet (30 m) thick in western part of quadrangle, interbedded with gypsum beds 3 to 10 feet (1 to 3 m) thick.
Womble Formation or Womble Shale (Phanerozoic | Paleozoic | Ordovician-Early Ordovician-Middle)
ARDMORE-SHERMAN- "Womble Shale"- Shale, black to green; thickness, 250 feet, base covered. Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- "Womble Formation"- Sandstone, phyllites, and shales, greenish-gray to dark-gray to black, weathering red-brown; some black to brown cherty limestones occur in upper part; Middle Ordovician graptolites are found in upper part, and Lower Ordovician graptolites in lower part; basal part faulted; estimated thickness, 1,000 feet or more, with maximum thickness in Arkansas 3,500 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS
Woodford Shale (Phanerozoic | Paleozoic | Devonian-Late Carboniferous Mississippian-Early)
McALESTER TEXARKANA- Shale and chert, black, fissile, with phosphatic nodules and some greenish-gray silty shale; at base is reddish-brown shale; rests on Pine Top Chert in Northeast quarter of section 5 of Township 2 North, Range 15 East; thickness, 67 feet at Pine Top. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.
Woodford Shale (Phanerozoic | Paleozoic | Devonian-Late)
ARDMORE-SHERMAN- Shale, black, fissile, cherty; thickness, 160 to 560 feet, increasing southward. Occurs in the ARBUCKLE MTNS

Oregon

Marine sedimentary rocks (Upper Triassic? and Upper and Middle Triassic) (Early Triassic)
Black, green, and gray argillite, mudstone, and shale; graywacke, sandy limestone, tuff, and some coarse volcaniclastic rocks; chert, sandstone comprised of chert clasts, and chert pebble conglomerate; thin-bedded and massive limestone. Locally contains some interbedded lava flows, mostly spilite or keratophyre. In places metamorphosed. Invertebrate marine fauna indicates unit mostly of Late Triassic (Karnian and Norian) age. Includes the Begg and Brisbois Formations of Dickinson and Vigrass (1965; Vester Formation of Brown and Thayer, 1966) and the Rail Cabin Argillite of Dickinson and Vigrass (1965); Fields Creek Formation and Laycock and Murderers Creek Graywackes of Brown and Thayer (1966); Martin Bridge Formation and lower sedimentary series in and near the Wallowa Mountains (Prostka, 1962; Nolf, 1966); and Doyle Creek and Wild Sheep Creek Formations (Vallier, 1977). Probably partly age correlative with rocks of the Applegate Group (Wells and Peck, 1961) of southwestern Oregon
Sedimentary rocks (Cretaceous) (Cretaceous)
Marine graywacke, subgraywacke, conglomerate, and shale. Pebbles and cobbles in conglomerate are well rounded volcanic and metavolcanic rocks, low-grade metasedimentary rocks, quartzite, chert, and minor silicic and intermediate plutonic rocks. Shales are gray to black and are fissile to blocky. Sandstones commonly display graded bedding; conglomerate beds are commonly thick and poorly bedded. Shales, near Mitchell, have yielded latest (Early Cretaceous (Albian) fossils; some earliest Late Cretaceous (Cenomanian) fossils occur in beds southeast of Mitchell (D.L. Jones, oral Commun., 1972). Includes Hudspeth and Gable Creek Formations (OR049), Bernard Formation (OR028), and Cretaceous sedimentary rocks (OR008)
Sedimentary rocks (Jurassic) (Jurassic)
Black and gray mudstone, shale, siltstone, graywacke, andesitic to dacitic water-laid tuff, porcelaneous tuff, and minor interlayers and lenses of limestone and fine-grained sediments metamorphosed to phyllite or slate. Locally includes some felsite, andesite and basalt flows, breccia, and agglomerate. Marine invertebrate fauna indicates age range from Early Jurassic (Hettangian) to early Late Jurassic (Oxfordian). In northeast Oregon, includes Graylock Formation, Mowich Group, and Shaw Member (of Snowshoe Formation) of Dickinson and Vigrass (1965); Keller Creek Shale of Brown and Thayer (1966); Weberg, Warm Springs, Snowshoe, Trowbridge, and Lonesome Formations of Lupher (1941); the Coon Hollow Formation of Morrison (1964); and unnamed Jurassic rocks near Juniper Mountain in northern Malheur County (Wagner and others, 1963)
Sedimentary rocks (Oligocene and upper Eocene) (Late Eocene to Oligocene)
Marine shale siltstone, sandstone, and conglomerate, in places partly composed of tuffaceous and basaltic debris; interbeds of arkosic, glauconitic, and quartzose sandstone. Foraminifers are referable to the Refugian and Zemorrian Stages (see marine sedimentary rocks-units Toes and Toem-of Wells and others, 1983). Includes Bastendorff Formation of Baldwin (1974)

Pennsylvania

Allegheny and Pottsville Formations, undivided (Pennsylvanian)
Allegheny and Pottsville Formations, undivided - Sandstone, shale, and some coal; includes lower Pottsville conglomerate and overlying strata equivalent to Allegheny Formation in north-central outliers; formational boundary not determined due to lack of correlation with Brookville-Clarion coal.
Allegheny Formation (Pennsylvanian)
Allegheny Formation - Cyclic sequences of sandstone, shale, limestone, clay, and coal; includes valuable clay deposits and Vanport Limestone; commercially valuable Freeport, Kittanning, and Brookville-Clarion coals present; base is at bottom of Brookville-Clarion coal.
Bald Eagle Formation (Ordovician)
Bald Eagle Formation - Gray to olive-gray and grayish-red, fine- to coarse-grained, crossbedded sandstone, siltstone, and shale; some conglomerate (Lost Run Member); not present east of Susquehanna River, except at Spitzenberg Hill area (Berks County).
Berea Sandstone through Riceville Formation, undivided (Devonian)
Berea Sandstone through Riceville Formation, undivided - Sandstone, siltstone, and shale; mostly light to dark gray, but some sandstone is greenish yellow, and a few reddish shales occur. Includes, in descending order: Berea Sandstone, Bedford Shale, Cussewago Sandstone, and Riceville Shale; marine fossils common.
Berea Sandstone through Venango Formation, undivided (Devonian)
Berea Sandstone through Venango Formation, undivided - Greenish-yellow and gray sandstone, siltstone, and shale succession, becoming more shaly and more gray downward; bottom of interval is bottom of Panama Conglomerate; Venango not mapped separately because upper key bed (Woodcock Sandstone) is missing. Includes, in descending order: Berea Sandstone, Bedford Shale, Cussewago Sandstone, Riceville Shale, and Venango Formation equivalent; contains marine fossils.
Bloomsburg and Mifflintown Formations, undivided (Silurian)
Bloomsburg and Mifflintown Formations, undivided - Includes, in descending order, the Bloomsburg Formation (Sb) and the Mifflintown Formation--interbedded dark-gray shale and medium-gray fossiliferous limestone; equivalent to "McKenzie" and "Rochester" of earlier workers; not present east of Harrisburg.
Bloomsburg Formation (Silurian)
Bloomsburg Formation - Grayish-red siltstone, shale, and sandstone arranged in fining-upward cycles.
Bloomsburg Formation (Silurian)
Bloomsburg Formation - Grayish-red and greenish-gray shale, siltstone, and very fine to coarse-grained sandstone; some calcareous mudstone in central Pennsylvania; thins to west and is replaced by Mifflintown beds; thickens eastward, replacing overlying Wills Creek and Tonoloway Formations and underlying Mifflintown Formation.
Brallier and Harrell Formations, undivided (Devonian)
Brallier and Harrell Formations, undivided - In descending order: Brallier--medium-gray, planar-bedded siltstone interbedded with light-olive shale; sparse marine fauna; Harrell--black shale (Burket Member) and dark-gray shale.
Brunswick Formation (Triassic)
Brunswick Formation - Reddish-brown mudstone, siltstone, and shale, containing a few green and brown shale interbeds; red and dark-gray, interbedded argillites near base. Youngest beds in Brunswick may be Jurassic in age.
Burgoon Sandstone (Mississippian)
Burgoon Sandstone - Buff, medium-grained, crossbedded sandstone; includes shale and coal; in places, contains conglomerate at base; contains plant fossils; equivalent to Pocono Formation of Ridge and Valley province.
Burgoon Sandstone through Cuyahoga Group, undifferentiated (Mississippian)
Burgoon Sandstone through Cuyahoga Group, undifferentiated - Informal unit including elements of Burgoon Sandstone and Shenango Formation plus Cuyahoga Group; correlation uncertain; contains sedimentary structures and trace fossils characteristic of tidal flats; called "Pocono" by earlier workers.
Buttermilk Falls Limestone through Esopus Formation, undivided (Devonian)
Buttermilk Falls Limestone through Esopus Formation, undivided - In descending order: Buttermilk Falls Limestone--gray fossiliferous limestone and black chert; Palmerton Sandstone--massive white siliceous sandstone; Schoharie Formation--gray calcareous, argillaceous siltstone; Esopus Formation--gray silty shale and sandy siltstone.
Casselman Formation (Pennsylvanian)
Casselman Formation - Cyclic sequences of shale, siltstone, sandstone, red beds, thin, impure limestone, and thin, nonpersistent coal; red beds are associated with landslides; base is at top of Ames limestone.
Catskill Formation (Devonian)
Catskill Formation - Succession of grayish-red sandstone, siltstone, shale, and mudstone, generally in fining-upward cycles; some gray sandstone and conglomerate.
Catskill Formation (Devonian)
Catskill Formation - Grayish-red sandstone, siltstone, shale, and mudstone; locally conglomeratic; contains gray sandstone in upper part; lithologies arranged in fining-upward cycles; equivalent to the Hampshire Formation south of Pennsylvania.
Catskill Formation (Devonian)
Catskill Formation - Grayish-red sandstone, siltstone, shale, and mudstone; units of gray sandstone occur in upper part; lithologies in upper part arranged in fining-upward cycles. In the Altoona area, the Catskill Formation is mapped as the Duncannon, Sherman Creek, and Irish Valley Members, which are described under "Central and Eastern Pennsylvania" provinces.
Chadakoin Formation (Devonian)
Chadakoin Formation - Light-gray or brownish siltstone and some sandstone, interbedded with medium-gray shale; included in Conneaut Group and "Chemung" of earlier workers; marine fossils common; includes "pink rock" of drillers.
Chambersburg Formation (Ordovician)
Chambersburg Formation - Dark-gray, cobbly, argillaceous limestone; abundant irregular shale partings; some metabentonite beds present.
Clinton Group (Silurian)
Clinton Group - Predominantly Rose Hill Formation--light-olive-gray to brownish-gray, fossiliferous shale; locally, limestone occurs near top; includes dark-reddish-gray, very fine to coarse-grained, ferruginous sandstone; east of Harrisburg, equivalent to Lizard Creek Member of Shawangunk Formation. Above Rose Hill is Keefer Formation--light- to dark-gray, fossiliferous sandstone, hematitic, oolitic sandstone, and shale; not recognized east of Harrisburg.
Coburn Formation through Loysburg Formation, undivided (Ordovician)
Coburn Formation through Loysburg Formation, undivided - Includes, in descending order, the Coburn Formation through Nealmont Formation, undivided (Ocn) and Benner Formation through Loysburg Formation, undivided (Obl).
Coburn Formation through Nealmont Formation, undivided (Ordovician)
Coburn Formation through Nealmont Formation, undivided - In descending order: Coburn Formation--medium-gray to very dark gray, very fossiliferous limestone and shaly limestone; Salona Formation--very dark gray to black, nonfossiliferous shaly limestone and calcareous shale containing metabentonite beds; Nealmont Formation--medium-gray fossiliferous limestone (calcarenite--Rodman Member) overlying thin-bedded shaly limestone (calcilutite--Center Hall Member).
Cocalico Formation (Ordovician)
Cocalico Formation - Gray phyllitic shale, maroon shale, siltstone, and silty, siliceous shale; some interbedded argillaceous and quartzose sandstone; predominantly allochthonous, and probably closely related to Hamburg sequence, but includes some autochthonous elements.
Conemaugh Group (Pennsylvanian)
Conemaugh Group - Includes, in descending order, the Casselman Formation (PAcc) and the Glenshaw Formation (PAcg), which are described separately below. Casselman: Cyclic sequences of shale, siltstone, sandstone, red beds, thin, impure limestone, and thin, nonpersistent coal; red beds are associated with landslides; base is at top of Ames limestone. Glenshaw: Cyclic sequences of shale, sandstone, red beds, and thin limestone and coal; includes four marine limestone or shale horizons; red beds are involved in landslides; base is at top of Upper Freeport coal.
Conestoga Formation (Ordovician and Cambrian)
Conestoga Formation - Light-gray, thin-bedded, impure, contorted limestone having shale partings; conglomeratic at base; in Chester Valley, includes micaceous limestone in upper part, phyllite in middle, and alternating dolomite and limestone in lower part.
Corry Sandstone through Riceville Formation, undivided (Devonian)
Corry Sandstone through Riceville Formation, undivided - Same as Berea-through-Riceville (MDbr) interval, but uppermost sandstone unit is recognized as Corry, not Berea.
Cuyahoga Group (Mississippian)
Cuyahoga Group - Medium-gray siltstone and dark-gray shale containing interbedded light-gray, flaggy sandstone. Includes, in descending order: Meadville Shale, Sharpsville Sandstone, and Orangeville Shale; marine fossils common.
Decker Formation through Poxono Island Formation, undivided (Silurian)
Decker Formation through Poxono Island Formation, undivided -In descending order: Decker Formation--gray calcareous sandstone having lenses of calcareous conglomerate, siltstone, and shale, and lenses of limestone and dolomite (in Stroudsburg area, includes calcareous shale, limestone, and dolomite of Rondout Formation at top); Bossardville Limestone--gray argillaceous limestone and dolomitic limestone; Poxono Island Formation--thin-bedded dolomite, limestone, and shale; red shale in lower part. This undivided succession is equivalent to Keyser, Tonoloway, and Wills Creek (part) Formations of central Pennsylvania.
Elbrook Formation (Cambrian)
Elbrook Formation - Light-colored calcareous shale and silty limestone at top; medium-gray limestone and dolomite in middle; pure, dark limestone at base.
Foreknobs Formation (Devonian)
Foreknobs Formation - Interbedded sandstone, siltstone, and shale; gray to olive gray, red near top; substantial brownish-gray sandstone; some marine fossils; a few conglomerate beds at base and top.
Gettysburg Formation (Triassic)
Gettysburg Formation - Reddish-brown to maroon, silty mudstone and shale containing thin red sandstone interbeds; several thin beds of impure limestone.
Girard Shale (Devonian)
Girard Shale - Argillaceous, ashen-gray, flaky shale and siltstone; included in Conneaut Group and "Chemung" of earlier workers; marine fossils rare.
Glenshaw Formation (Pennsylvanian)
Glenshaw Formation - Cyclic sequences of shale, sandstone, red beds, and thin limestone and coal; includes four marine limestone or shale horizons; red beds are involved in landslides; base is at top of Upper Freeport coal.
Graywacke and shale of Martinsburg Formation (Ordovician)
Graywacke and shale of Martinsburg Formation - Shale containing conspicuous graywacke; includes autochthonous sandstone and shale of Shochary Ridge.
Greene Formation (Permian)
Greene Formation - Cyclic sequences of sandstone, shale, red beds, thin limestone, and thin, impure coal; base is at top of Upper Washington limestone.
Hamburg sequence rocks (Ordovician)
Hamburg sequence rocks - Predominantly greenish gray, gray, purple, and maroon shale, siltstone, and graywacke; includes some wildflysch having Martinsburg matrix.
Hamilton Group (Devonian)
Hamilton Group - Includes, in descending order, the Mahantango (Dmh) and Marcellus (Dmr) Formations.
Heidlersburg Member of Gettysburg Formation (Triassic)
Heidlersburg Member of Gettysburg Formation - Red, green, and gray shale and argillite, and minor thin beds of gray arkosic sandstone; some quartz conglomerate and limestone conglomerate.
Huntley Mountain Formation (Mississippian and Devonian)
Huntley Mountain Formation - Greenish-gray and light-olive-gray, flaggy, fine-grained sandstone, siltstone, and a few red shale interbeds; includes lower "Pocono" plus "Oswayo" of earlier workers. Forms transition between Catskill Formation and Burgoon Sandstone.
Jacksonburg Formation (Ordovician)
Jacksonburg Formation - Dark-gray shaly limestone (cement rock) having slaty cleavage; basal medium- to thick-bedded limestone (cement limestone) increases in thickness eastward.
Juniata and Bald Eagle Formations, undivided (Ordovician)
Juniata and Bald Eagle Formations, undivided - Includes, in descending order, the Juniata (Oj) and Bald Eagle (Obe) Formations.
Juniata Formation (Ordovician)
Juniata Formation - Grayish-red, very fine to medium-grained, crossbedded sandstone, and grayish-red siltstone and shale; merges with underlying Bald Eagle Formation to the south; not present east of Susquehanna River, except at Spitzenberg Hill area (Berks County).
Keyser and Tonoloway Formations, undivided (Devonian and Silurian)
Keyser and Tonoloway Formations, undivided - In descending order: Keyser Formation--medium-gray, crystalline to nodular, fossiliferous limestone; upper part laminated and mud-cracked; not present east of Harrisburg; passes into lower Coeymans, Rondout, and Decker Formations in the east. Tonoloway Formation--medium-gray, laminated, mud-cracked limestone containing some medium-dark- or olive-gray shale interbeds; lower part passes into Wills Creek Formation east and south; passes into Bossardville and Poxono Island beds in the east.
Keyser Formation through Clinton Group, undivided (Devonian and Silurian)
Keyser Formation through Clinton Group, undivided - Same as Keyser-through-Mifflintown (DSkm) interval, plus Clinton Group at base. Clinton includes the following, in descending order: Keefer Formation--fossiliferous sandstone and hematitic, oolitic sandstone and shale; Rose Hill Formation--fossiliferous shale.
Keyser Formation through Mifflintown Formation, undivided (Devonian and Silurian)
Keyser Formation through Mifflintown Formation, undivided - In descending order: Keyser Formation--limestone; Tonoloway Formation--limestone and interbedded shale; Wills Creek Formation--interbedded shale, siltstone, limestone, and dolomite; Bloomsburg Formation--grayish-red and greenish-gray shale, siltstone, sandstone, and mudstone; Mifflintown Formation--interbedded shale and limestone.
Kinzers Formation (Cambrian)
Kinzers Formation - Base--dark-brown shale; middle--gray and white spotted limestone and, locally, marble having irregular partings; top--sandy limestone which weathers to a fine-grained, friable, porous, sandy mass.
Leithsville Formation (Cambrian)
Leithsville Formation - Medium- to dark-gray, crystalline dolomite, light-olive-gray in places, weathering to light gray and yellowish brown; massive bedded; oolitic; pink to gray, mottled chert and dark-gray chert; thin shale and dolomitic shale interbeds; scattered sand grains; upper part is very shaly.
Limestone fanglomerate (Triassic)
Limestone fanglomerate - Yellowish-gray to medium-gray, angular limestone and dolomite pebbles, cobbles, and fragments set in a red, very fine grained quartz matrix; a few shale-clast interbeds.
Limestone of Martinsburg Formation (Ordovician)
Limestone of Martinsburg Formation - Dark-gray, thin-bedded, platy argillaceous limestone containing some beds of shale.
Llewellyn Formation (Pennsylvanian)
Llewellyn Formation - Gray, fine- to coarse-grained sandstone, siltstone, shale, conglomerate, and numerous anthracite coals in repetitive sequences.
Lockatong Formation (Triassic)
Lockatong Formation - Dark-gray to black, thick-bedded argillite containing a few zones of thin-bedded black shale; locally has thin layers of impure limestone and calcareous shale.
Lower (Middle?) Cambrian rocks, undivided (Cambrian)
Lower (Middle?) Cambrian rocks, undivided - Lower Cambrian of Berks County includes tectonic slices of many of the following rock units: Zooks Corner (CAzc), Ledger (CAl), Kinzers (CAk), Vintage (CAv), Antietam (CAa, CAah), and Harpers (CAh, CAah) Formations.
Mahantango Formation (Devonian)
Mahantango Formation - Gray, brown, and olive shale and siltstone; marine fossils. Includes the following members, in descending order: Tully-argillaceous limestone; Sherman Ridge, Montebello (sandstone), Fisher Ridge, Dalmatia, and Turkey Ridge. In south-central Pennsylvania, includes Clearville, Frame, Chaneysville, and Gander Run Members. Characterized by coarsening-upward cycles.
Martinsburg Formation (Ordovician)
Martinsburg Formation - Gray to dark-gray shale and slate.
Martinsburg Formation (Ordovician)
Martinsburg Formation - Gray to dark-gray, buff-weathering shale.
Martinsburg Formation (Ordovician)
Martinsburg Formation - Dark-gray, slaty to phyllitic shale, calcareous at base. Probably only lower part of Martinsburg Formation is present; overlain by Hamburg sequence rocks.
Mauch Chunk Formation (Mississippian)
Mauch Chunk Formation - Grayish-red shale, siltstone, sandstone, and some conglomerate; some local nonred zones. Includes Loyalhanna Member (crossbedded, sandy limestone) at base in south-central and southwestern Pennsylvania; also includes Greenbrier Limestone Member, and Wymps Gap and Deer Valley Limestones, which are tongues of the Greenbrier. Along Allegheny Front from Blair County to Sullivan County, Loyalhanna Member is greenish-gray, calcareous, crossbedded sandstone.
Millbach and Schaefferstown Formations, undivided (Cambrian)
Millbach and Schaefferstown Formations, undivided - Includes, in descending order, the Millbach Formation (CAm), and the Schaefferstown Formation--gray limestone containing siliceous and argillaceous laminae; thin bedded.
Monongahela Group (Pennsylvanian)
Monongahela Group - Cyclic sequences of limestone, shale, sandstone, and coal; commercial coals present; base is at bottom of Pittsburgh coal.
New Oxford Formation (Triassic)
New Oxford Formation - Light-gray to buff, commonly arkosic sandstone interbedded with red shale, mudstone, and fine-grained sandstone
Northeast Shale (Devonian)
Northeast Shale - Medium-gray shale and some thin light-gray siltstone interbeds; included in Canadaway Formation of New York; included in "Chemung" of earlier workers; contains sparse fossil marine fauna.
Onondaga and Old Port Formations, undivided (Devonian)
Onondaga and Old Port Formations, undivided - Includes, in descending order, the Onondaga Formation (Don), Ridgeley Member of Old Port Formation (Dor), and Shriver, Mandata, Corriganville, and New Creek Members of Old Port Formation, undivided (Dosn).
Onondaga Formation (Devonian)
Onondaga Formation - Medium-gray calcareous shale; marine fossils; medium-gray argillaceous limestone of Selinsgrove Member at top; called "Needmore Formation" west of 78° longitude; Tioga bentonite at top.
Onondaga Formation through Poxono Island Formation, undivided (Devonian and Silurian)
Onondaga Formation through Poxono Island Formation, undivided - In descending order: Onondaga Formation--gray calcareous, sandy shale; Ridgeley Formation--brown sandstone; Rondout Formation--gray interbedded limestone, dolomite, and shale; Decker Formation--gray calcareous sandstone, and Andreas Red Beds at top; Bossardville Limestone--gray, mud-cracked shaly limestone; Poxono Island Formation--olive-gray, calcareous and dolomitic shale, siltstone, and sandstone.
Pleasant Hill Formation (Cambrian)
Pleasant Hill Formation - Gray, thin-bedded, argillaceous limestone interbedded with shale, siltstone, and sandstone.
Pocono and Rockwell Formations, undivided (Mississippian and Devonian)
Pocono and Rockwell Formations, undivided: Buff, medium-grained, crossbedded sandstone and some conglomerate (Pocono), overlying buff to olive-gray, fine- to medium-grained, crossbedded sandstone containing a few beds of shale and conglomerate (Rockwell); shown in southwestern Bedford County only.
Pottsville Formation (Pennsylvanian)
Pottsville Formation - Predominantly gray sandstone and conglomerate; also contains thin beds of shale, claystone, limestone, and coal; includes Olean and Sharon conglomerates of northwestern Pennsylvania; thin marine limestones present in Beaver, Lawrence, and Mercer Counties; minable coals and commercially valuable high-alumina clays present locally.
Pottsville Formation (Pennsylvanian)
Pottsville Formation - Gray conglomerate, fine- to coarse-grained sandstone, and siltstone and shale containing minable anthracite coals. Includes three members, in descending order: Sharp Mountain--conglomerate and conglomeratic sandstone; Schuylkill--sandstone and conglomeratic sandstone; Tumbling Run--conglomeratic sandstone and sandstone.
Reedsville Formation (Ordovician)
Reedsville Formation - Olive-gray to dark-gray shale, siltstone, and fine-grained, thin-bedded sandstone having graded bedding; upper sandstone is very fossiliferous; includes Antes Formation (black calcareous shale) at base along Nittany Arch.
Ridgeley Formation through Coeymans Formation, undivided (Devonian)
Ridgeley Formation through Coeymans Formation, undivided - In descending order: Ridgeley Formation--white siliceous sandstone; Shriver Chert--gray siltstone and shale and dark-gray chert; Port Ewen Shale--dark-gray calcareous siltstone and shale; Minisink Limestone--dark-gray clayey limestone; New Scotland Formation--dark-gray fossiliferous shale and clayey limestone; Coeymans Formation--gray, clayey to sandy limestone.
Rockwell Formation (Mississippian and Devonian)
Rockwell Formation - Buff, fine- to medium-grained, crossbedded, argillaceous sandstone and dark-gray shale; includes some carbonaceous shale, sporadic conglomerate beds, and diamictite; included in lower "Pocono" of earlier workers.
Scherr Formation (Devonian)
Scherr Formation - Chiefly siltstone; some fine-grained sandstone, shale, and mudstone; light olive gray; marine fossils.
Sedimentary strata at Jacksonwald and Aspers (Jurassic)
Sedimentary strata at Jacksonwald and Aspers - Arkosic sandstone; fossiliferous, gray to black shale and limestone; ripple-cross-laminated siltstone; and boulder conglomerate.
Shale and graywacke of Hamburg sequence (Ordovician)
Shale and graywacke of Hamburg sequence - Shale containing zones of conspicuous graywacke.
Shawangunk Formation (Silurian)
Shawangunk Formation - Light- to dark-gray, fine- to very coarse grained sandstone and conglomerate containing thin shale interbeds. Includes four members, in descending order: Tammany--conglomerate and sandstone; Lizard Creek--sandstone and red or green shale; Minsi--sandstone and conglomerate; Weiders--conglomerate. Tammany and Lizard Creek Members together are approximately equivalent to Clinton Group to the west; Minsi and Weiders Members together are equivalent to Tuscarora Formation to the west.
Shenango Formation (Mississippian)
Shenango Formation - Light-gray sandstone and some beds of medium-gray shale and siltstone; upper third of formation is more shaly; contains a few marine fossils.
Shenango Formation through Cuyahoga Group, undivided (Mississippian)
Shenango Formation through Cuyahoga Group, undivided - includes the Shenango Formation (Ms) and Cuyahoga Group (Mc), which are described separately below. Shenango: Light-gray sandstone and some beds of medium-gray shale and siltstone; upper third of formation is more shaly; contains a few marine fossils. Cuyahoga: Medium-gray siltstone and dark-gray shale containing interbedded light-gray, flaggy sandstone. Includes, in descending order: Meadville Shale, Sharpsville Sandstone, and Orangeville Shale; marine fossils common.
Shenango Formation through Oswayo Formation, undivided (Mississippian and Devonian)
Shenango Formation through Oswayo Formation, undivided - Greenish-gray, olive, and buff sandstone and siltstone, and gray shale in varying proportions; includes "Pocono" ("Knapp") and Oswayo of earlier workers; difficult lithologic distinction between Oswayo and "Knapp"- "Pocono" south and east of type area at Olean, N. Y.; contains marine fossils; includes lateral equivalents of Shenango Formation, Cuyahoga Group, Corry Sandstone, Bedford Shale, and Cussewago Sandstone, plus Oswayo Formation.
Shenango Formation through Riceville Formation, undivided (Mississippian and Devonian)
Shenango Formation through Riceville Formation, undivided - Sandstone, siltstone, and shale in varying proportions; distinguished from Shenango-through-Oswayo (MDso) interval on basis of more common gray shale in Riceville as compared with olive-colored shale and sandstone of Oswayo; contains marine fossils.
Shriver, Mandata, Corriganville, and New Creek Members of Old Port Formation, undivided (Devonian)
Shriver, Mandata, Corriganville, and New Creek Members of Old Port Formation, undivided - Limestone, chert, shale, and siliceous siltstone. In Fulton County, limestone and chert of the Licking Creek Member replaces the Shriver and Mandata.
Spechty Kopf Formation (Mississippian and Devonian)
Spechty Kopf Formation - Light- to olive-gray, fine- to medium- grained, crossbedded sandstone, siltstone, and local polymictic diamictite, pebbly mudstone, and laminite; arranged in crude fining-upward cycles in some places; locally has grayish-red shale near top and conglomerate at base and in middle.
Tomstown Formation (Cambrian)
Tomstown Formation - Massive dolomite containing thin shaly interbeds.
Towamensing Member of Catskill Formation (Devonian)
Towamensing Member of Catskill Formation - Dominantly gray sandstone and some siltstone and shale; freshwater fossils.
Trimmers Rock Formation (Devonian)
Trimmers Rock Formation - Olive-gray siltstone and shale, characterized by graded bedding; marine fossils; some very fine grained sandstone in northeast; black shale of Harrell Formation at base in Susquehanna Valley.
Tuscarora Formation (Silurian)
Tuscarora Formation - Light- to medium-gray quartzite and quartzitic sandstone and minor interbedded shale and siltstone, locally conglomeratic in lower part; includes (to the northwest) interbedded red and non-red sandstone (Castanea Member) at top; east of Harrisburg, equivalent to Minsi and Weiders Members of Shawangunk Formation.
Venango Formation (Devonian)
Venango Formation - Light-gray siltstone interbedded with some flaggy, gray sandstone and some bluish-gray shale; Panama Conglomerate and Woodcock Sandstone are, respectively, the lower and upper key beds defining the formation; referred to as "Cattaraugus" by some workers; includes some red shales where it interfingers to the east and south with the Catskill Formation; marine fossils present.
Walcksville and Towamensing Members of Catskill Formation, undivided (Devonian)
Walcksville and Towamensing Members of Catskill Formation, undivided - Includes, in descending order, the Walcksville Member (Dcw) of the Catskill Formation, and the Towamensing Member (Dct).
Washington Formation (Permian)
Washington Formation - Cyclic sequences of sandstone, shale, limestone, and coal; includes some red shale; base is at bottom of Washington coal.
Waynesboro Formation (Cambrian)
Waynesboro Formation - Interbedded red to purple shale and sandstone and some beds of dolomite and impure limestone.
Waynesboro Formation (Cambrian)
Waynesboro Formation - Greenish-gray and grayish-purple shale interbedded with greenish-gray sandstone and conglomerate; occurs in Henrietta fault block only.
Waynesburg Formation (Permian and Pennsylvanian)
Waynesburg Formation - Cyclic sequences of sandstone, shale, limestone, and coal; commercial coals present; base is at bottom of Waynesburg coal.
Wills Creek Formation (Silurian)
Wills Creek Formation - Variegated gray, grayish-red, yellowish-gray and greenish-gray, interbedded calcareous shale, siltstone, shaly limestone, and dolomite; passes into Bloomsburg Formation in the southeast; not present east of Harrisburg.
Wills Creek Formation through Mifflintown Formation, undivided (Silurian)
Wills Creek Formation through Mifflintown Formation, undivided - Includes, in descending order, the Wills Creek Formation (Swc) and Bloomsburg and Mifflintown Formations, undivided (Sbm).

Rhode Island

South Dakota

Belle Fourche Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Dark-gray to black bentonitic shale containing minor limestone lenses, bentonite layers, fossiliferous calcarenite, and large, ferruginous, carbonate concretions. Thickness 150-350 ft (46-107 m).
Belle Fourche Shale, Mowry Shale, Newcastle Sandstone,and Skull Creek Shale (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Middle(?) Cretaceous-Late)
Note: see individual unit descriptions
Carlile Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Dark-gray to black, silty to sandy shale with several zones of septarian, fossiliferous, carbonate concertions. Contains up to three sandstone beds near the middle of the formation and sandy calcareous marl at the base. Thickness 345-620 ft (105-189 m).
Fox Hills Sandstone (Phanerozoic | Mesozoic | Cretaceous-Late)
Bluish-green to green, white to dark-gray, yellow to tan, carbonaceous and iron-stained, cross-bedded, very fine- to coarse-grained, glaconitic sandstone and siltstone. Interbedded with gray and green to brown shale and silty shale. Thickness 25-400 ft (8-122 m).
Greenhorn Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Gray shale, mudstone, marl, calcarenite, and shaley limestone grading upward into light-gray to tan, alternating marl and thin-bedded, fossiliferous limestone. Thickness 225-315 ft (69-96 m).
Greenhorn Formation, Belle Fourche Shale, Mowry Shale, Newcastle Sandstone, Skull Creek Shale, Inyan Kara Group, Morrison Formation, Unkpapa Sandstone, Sundance Formation, Spearfish Formation, Minnekahta Limestone, Opeche Shale, Minnelusa Formation, and Pahasapa Limestone (Phanerozoic | Paleozoic Mesozoic | Carboniferous Mississippian Permian(?) Triassic(?) Jurassic(?) Cretaceous-Early(?) Cretaceous-Middle(?) Cretaceous-Late)
Note: see individual unit descriptions
Hell Creek Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Tan to brown, light- to dark-gray, "somber beds" of shale. Interbedded with brown to red carbonaceous shale, gray and brown bentonitic silty shale, and gray, brown and yellow siltstone, sandstone, and claystone-pebble conglomerate. Thickness 260-600 ft (79-183 m).
Inyan Kara Group (Phanerozoic | Mesozoic | Cretaceous-Early )
Includes: Fall River Formation- Variegated brown, red, gray to purple, calcareous, well-sorted, fine-grained sandstone, siltstone, and shale containing mica flakes. Thickness 100-200 ft (30-61 m). Lakota Formation- Yellow, brown, red-brown, gray to black silty shale, pebble conglomerate, and massive to thin-bedded, cross-bedded sandstone. Locally interbedded with fresh-water limestone and bituminous coal beds. Thickness 35-500 ft (11-152 m).
Minnekahta Limestone and Opeche Shale (Phanerozoic | Paleozoic | Permian)
Minnekahta Limestone-Purple to gray, finely crystalline, thin- to medium-bedded limestone with varying amounts of red shale. Thickness 30-50 ft (9-15 m). Opeche Shale- Red siltstone, argillaceous sandstone and shale interbedded with caliche layers. Thickness 85-130 ft (26-40 m).
Minnelusa Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian)
Variegated, yellow to red, gray to brown, pink to purple, and black, interbedded sandstone, siltstone, shale, limestone, dolomite, calcarenite, chert and brecciated beds. Thickness 394-1,175 ft (120-358 m).
Morrison Formation, Unkpapa Sandstone, Sundance Formation, and Gypsum Spring Formation (Phanerozoic | Mesozoic | Jurassic-Middle Jurassic-Late)
Morrison Formation (Late Jurassic)- Light-gray to green and variegatedred, brown, yellow, or lavender, silceous claystone, shale, and siltstone containing interbedded sandstone and fresh-water limestone lenses. Thickness up to 150 ft (46 m). Unkpapa Sandstone (Late Jurassic)- White, massive to thin-bedded, fine-grained, argillaceous sandstone. May be variegated to banded red, yellow, brown, or lavender. Thickness up to 267 ft (81 m). Sundance Formation (Late to Middle Jurassic)- Greenish-gray, yellow, tan, red to orange, and white, variegated, interbedded, fine- to coarse-grained sandstone, siltstone, clay, and limestone. Thickness 250-350 ft (76-107 m). Gypsum Springs Formation (Middle Jusassic)- Massive white gypsum and minor maroon siltstone and shale. Thickness up to 40 ft (12 m).
Mowry Shale, Newcastle Sandstone, and Skull Creek Shale (Phanerozoic | Mesozoic | Cretaceous-Early )
Mowry Shale- Black to gray, siliceous, fissile shale and siltstone containing bentonite layers, and sparse sandstone dikes and sills. Thickness 125-250 ft (38-76 m). Newcastle Sandstone- Gray, light-brown to yellow, discontinuously distributed siltstone, claystone, sandy shale, and fine-grained sandstone. Thickness up to 290 ft (88 m). Skull Creek Shale- Dark-gray to blueish-gray shale containing ferruginous, and carbonate concretions. Thickness 150-275 ft (46-84 m).
Niobrara Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
White to dark gray argillaceous chalk, marl, and shale. Weathers yellow to orange. Contains thin, laterally continuous bentonite beds, chalky carbonaceous shale, minor sand, and small concretions. Thickness 160-225 ft (49-69 m).
Pahasapa Limestone, Englewood Formation, Whitewood Limestone, Winnipeg Formation, and Deadwood Formation (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian(?) Devonian(?) Carboniferous Mississippian)
Note: see individual descriptions
Pierre Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
Blue-gray to dark-gray, fissile to blocky shale with persistent beds of bentonite, black organic shale, or light-brown chalky shale. Contains minor sandstone, conglomerate, and abundant carbonate and ferruginous concretions. Thickness 1,000-2,700 ft (305-823 m).
Spearfish Formation (Phanerozoic | Paleozoic Mesozoic | Permian Triassic)
Red sandy shale, siltstone, sandstone, and minor limestone. Interbedded with abundant gypsum. Thickness 328-559 ft (100-170 m).
Whitewood Limestone, Winnipeg Formation, and Deadwood Formation (Phanerozoic | Paleozoic | Cambrian Ordovician)
Whitewood Limestone (Ordovician)- Mottled, tan, gray to lavender, fine- to medium-crystalline, sparsely fossiliferous limestone and dolomite. Thickness up to 70 ft (21 m). Winnipeg Formation (Ordovician)- Grat and light-green, fissile shale, and tan, calcareous siltstone, sandy shale, and limestone lenses. Thickness up to 110 ft (34 m). Deadwood Formation (Ordovician to Cambrian)- Variegated, yellow to red, brown, gray, and green, glauconitic, conglomerate, sandstone, shale, dolomitic limestone, and dolomite. Thickness 4-400 ft (1-122 m).

Tennessee

Athens Shale (Ordovician)
Athens Shale - Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of shaly limestone near base. Maximum thickness 1,500 feet.
Athens Shale (Ordovician)
Athens Shale - Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of shaly limestone near base. Maximum thickness 1,500 feet.
Bangor Limestone and Hartselle Formation (Mississippian)
Bangor Limestone - Dark brownish-gray limestone, thick-bedded. Thickness 100 to 250 feet; and Hartselle Formation - Thin-bedded, fine-grained sandstone and greenish-gray shale interbedded with coarse limestone. Thickness 0 to 60 feet.
Bangor Limestone and Hartselle Formation (Mississippian)
Bangor Limestone - Dark brownish-gray limestone, thick-bedded. Thickness 70 to 400 feet., and Hartselle Formation - Thin-bedded, fine-grained sandstone interbedded with gray shale; with oolitic and coarse-grained limestone beds locally. Thickness 0 to 80 feet.
Bigby-Cannon Limestone and Hermitage Formation (Ordovician)
Bigby-Cannon Limestone - Dark- to light-gray, dense to medium-grained, medium- and even-bedded limestone. Thickness 80 to 150 feet; and Hermitage Formation - Gray, fine-grained, thin-bedded to laminated, sandy and argillaceous limestone; shale, weathers yellowish-brown; and nodular, shaly limestone. Thickness 50 to 100 feet.
Chickamauga Group, includes Upper part of Chickamauga Group (Reedsville Shale, and Unnamed limestone unit) and Middle and Lower part of Chickamauga Group (Moccasin Formation, Bays Formation, Ottosee Shale, Holston Formation, Lenoir Limestone, Athens Shale, and Sevier Shale) (Ordovician)
Chickamauga Group - In the northwest part of the Valley and Ridge a predominantly limestone sequence about 2,000 feet thick. Becomes progressively more clastic and thicker to the southeast, including Upper part of Chickamauga Group (Reedsville Shale- Greenish-gray calcareous shale. Thickness 0 to 400 feet, and Unnamed Limestone Unit - Medium-grained, fossiliferous, gray limestone, shaly in part. Thickness as much as 600 feet ) and.Middle and lower parts of Chickamauga Group (Omlc)
Chilhowee Group; Cochran Conglomerate (Cambrian)
Chilhowee Gourp; Cochran Conglomerate - Quartz-pebble conglomerate, gray pebbly arkose, siltstone and shale; irregular bedding, scour features, crossbedding common; maroon micaceous arkose and shale near middle and base. Thickness about 1,200 feet.
Chilhowee Group; Hesse Sandstone (Cambrian)
Chilhowee Group; Hesse Sandstone - White, vitreous quartzite, medium- to coarse-grained, occurs in massive ledges; Helenmode Member at top is gray to greenish sandstone and shale. Thickness about 600 feet.
Chilhowee Group, including Erwin Formation, Hesse Sandstone, Murray Shale, Nebo Sandstone, Nichols Shale, Cochran Conglomerate, Hampton Formation, and Unicoi Formation (Cambrian)
Chilhowee Group - Conformable sequence of dominantly clastic sediments. Thickness 3,000 to 7,500 feet; including Erwin Formation - White, vitreous quartzite, massive, with interbeds of dark-green silty and sandy shale, minor siltstone, and very fine-grained sandstone. Thickness 1,000 to 1,500 feet; Hesse Sandstone - White, vitreous quartzite, medium- to coarse-grained, occurs in massive ledges; Helenmode Member at top is gray to greenish sandstone and shale. Thickness about 600 feet; Murray Shale - Shale, silty, sandy, dull-green to brown, micaceous. Thickness about 500 feet; Nebo Sandstone - Medium-bedded, fine-grained, white, vitreous quartzite, in part feldspathic. Thickness 250 feet; Nichols Shale - Olive-gray to green, silty and sandy, micaceous shale and siltstone; local lenses of fine-grained feldspathic quartzite. Thickness about 700 feet; Cochran Conglomerate - Quartz-pebble conglomerate, gray pebbly arkose, siltstone and shale; irregular bedding, scour features, crossbedding common; maroon micaceous arkose and shale near middle and base. Thickness about 1,200 feet; Hampton Formation - Dark greenish-gray, silty and sandy, micaceous shale; numerous layers of medium-grained, feldspathic, thinly bedded sandstone. Thickness 500 to 2,000 feet; Unicoi Formation - Sequence of gray feldspathic sandstone, arkose, conglomerate, graywacke, siltstone and shale; greenish amygdaloidal basalt flows near middle and base. Thickness 2,000 to 5,000 feet.
Chilhowee Group; Murray Shale (Cambrian)
Chilhowee Group; Murray Shale - Shale, silty, sandy, dull-green to brown, micaceous. Thickness about 500 feet.
Clinch Sandstone (Silurian)
Clinch Sandstone - Clean, white, well-sorted sandstone; locally gray siltstone and shale. Average thickness about 600 feet.
Cochran Conglomerate (Cambrian)
Cochran Conglomerate - Quartz-pebble conglomerate, gray pebbly arkose, siltstone and shale; irregular bedding, scour features, crossbedding common; maroon micaceous arkose and shale near middle and base. Thickness about 1,200 feet.
Conasauga Group (Cambrian)
Conasauga Group - Mostly shale northwest of a line connecting Knoxville and Tazewell; dominantly dolomite with minor shale southeast of a line from Newport to Kingsport; between these lines it consists of six formations. Thickness about 2,000 feet.
Conasauga Group, includes Maynardville Limestone, Nolichucky Shale, Honaker Dolomite, Maryville Limestone, Rogersville Shale, Rutledge Limestone, Pumpkin Valley Shale, Rome Formation, Shady Dolomite (Cambrian)
Conasauga Group, includes Maynardville Limestone, Nolichucky Shale, Honaker Dolomite, Maryville Limestone, Rogersville Shale, Rutledge Limestone, Pumpkin Valley Shale, Rome Formation, Shady Dolomite
Conasauga Group, including Maynardville Limestone, Nolichucky Shale, the Maryville, Rogersville, and Rutledge Formations, Pumpkin Valley Shale, Rome Formation, and Shady Dolomite (Cambrian)
Conasauga Group - Mostly shale northwest of a line connecting Etowah and Bearden (Knoxville); to the east it consists of the six formations at right [Cmn, Maynardville Limestone. Ccl including Cn, Nolichucky Shale, Cmr Maryville, Rogersville, and Rutledge Formations, and Pumpkin Valley Shale; Cr, Rome Formation, and Cs, Shady Dolomite. Thickness about 2,000 feet.
Crab Orchard Mounatins and Gizzard Group (Pennsylvanian)
Crab Orchard Mountains and Gizzard Groups - Sandstone, conglomerate, siltstone, shale, and thin coal beds. From top down Crab Orchard Mountains group includes Rockcastle Conglomerate, Vadever Formation, Newton Sandstone, Whitwell Shale, and Sewanee Conglomerate; Gizzard Group includes Signal Point Shale, Warren Point Sandstone, and Raccoon Mountain Formation. Thickness about 1,200 to 1,400 feet.
Crab Orchard Mountains and Gizzard Groups (Pennsylvanian)
Crab Orchard Mountains and Gizzard Groups - Sandstone, conglomerate, siltstone, shale, and thin coal beds. Thickness 1,200 to 1,400 feet.
Crab Orchard Mountains Group, including Rockcastle Conglomerate, Vandever Formation, Newton Sandstone, Whitwell Shale, and Sewanee Conglomerate (Pennsylvanian)
Crab Orchard Mountains Group - Conglomerate, sandstone, siltstone, shale, and coal; from top of Rockcastle Conglomerate to base of Sewanee Conglomerate. Thickness 200 to 950 feet; including Rockcastle Conglomerate - Conglomeratic sandstone and sandstone, gray to brown, fine- to coarse-grained. Thin coal-bearing shale locally present near middle. Thickness 150 to 220 feet; Vandever Formation - Mostly shale and siltstone, dark-gray to light-brown; conglomerate or sandstone in middle to south. Lantana and Morgan Springs coals near base and top. Thickness as much as 450 feet, average about 300 feet; Newton Sandstone - Sandstone, gray to brown or pink, fine- to medium-grained, locally conglomeratic. Thickness as much as 200 feet; average about 90 feet; Whitwell Shale - Mostly dark-gray to light-brown shale, with minor siltstone; locally middle part is sandstone. Richland coal near base; Sewanee coal in upper part. Thickness as much as 220 feet, average about 75 feet; Sewanee Conglomerate - Conglomeratic sandstone and sandstone, gray to brown, fine- to coarse-grained. Thickness as much as 200 feet, average about 100 feet.
Crooked Fork Group (Pennsylvanian)
Crooked Fork Group - Shale, sandstone, siltstone, and thin coal beds; from top down group includes Poplar Creek coal, Wartburg Sandstone, Glenmary Shale, Coalfield Sandstone, Burnt Mill Shale, Crossville Sandstone, and Dorton Shale. Thickness 200 to 450 feet.
Crooked Fork Group, including Wartburg Sandstone, Glenmary Shale, Coalfield Sandstone, Burnt Mill Shale, Crossville Sandstone, Dorton Shale (Pennsylvanian)
Crooked Fork Group - Shale, sandstone, conglomerate, siltstone, and coal; from Poplar Creek coal to top of Rockcastle Conglomerate. Thickness 320 to 455 feet; Wartburg Sandstone - Sandstone, gray to brown, fine- to medium-grained, locally conglomeratic. Poplar Creek coal and thin shale at top. Thickness 0 to 50 feet; Glenmary Shale - Mostly dark-gray to light-brown shale with minor siltstone and sandstone. Thin coal near base locally. Thickness 50 to 150 feet; Coalfield Sandstone - Sandstone, gray to brown, fine- to medium-grained. Thickness 0 to 80 feet; Burnt Mill Shale - Mostly dark-gray to light-brown shale, with minor siltstone. Thin sandstone locally present near base. Hooper coal just above base. Thickness as much as 110 feet; Crossville Sandstone - Sandstone, gray to brown or pink, fine- to medium-grained, thinly and evenly bedded. Thickness 30 to 70 feet; Dorton Shale - Mostly dark-gray to light-brown shale, with minor siltstone and sandstone. Thin coal near top. Rex coal as much as 70 feet above base. Thickness as much as 150 feet.
Cross Mountain Formation (Pennsylvanian)
Cross Mountain Formation - Mostly shale, interbedded with sandstone, siltstone, and thin coal beds; base at top of Frozen Head Sandstone. Maximum preserved thickness 554 feet.
Cross Mountain Formation (Pennsylvanian)
Cross Mountain Formation - Mostly shale, interbedded with sandstone, siltstone, and thin coal beds; base at top of Frozen Head Sandstone. Maximum preserved thickness 270 feet.
Devonian Formations, includes Pegram Formation, Camden Formation, Harriman Formation, Flat Gap Limestone, and Ross Formation (Devonian)
Devonian Formations - Characterized by marked north-south facies variations. Because of pre-Chattanooga and/or pre-Cretaceous warping and erosion, the distribution and thickness of Devonian formations is very irregular. Includes Pegram Formation - Thick-bedded, gray limestone and gray sandstone. Thickness 0 to 15 feet; Camden Formation - Light-gray novaculitic chert and tripolitic clay; and minor siliceous limestone. Thickness 0 to about 100 feet; Harriman Formation - Light-gray novaculitic chert and tripolitic clay; and minor siliceous limestone. (Harriman and Camden are differentiated paleontologically.) Thickness 0 to 50 feet; Flat Gap Limestone - Thick-bedded, coarse-grained limestone, gray with red and brown grains. Thickness 0 to 55 feet; Ross Formation - Siliceous limestone; gray and variegated shale; and medium-grained glauconitic limestone. Thickness 0 to 75 feet.
Devonian Formations, including Pegram Formation, Camden Formation, Harriman Formation, Flat Gap Limestone, and Ross Formation (Devonian)
Devonian Formations - Characterized by marked north-south facies variations and by very irregular distribution. Individual formations are not uniform in thickness and have been truncated by pre-Chattanooga erosion; includes Pegram Formation - Thick-bedded, gray limestone and gray sandstone. Thickness 0 to 30 feet; Camden Formation - Light-gray novaculitic chert and tripolitic clay; and minor siliceous limestone. Thickness 0 to about 100 feet; Harriman Formation - Light-gray novaculitic chert and tripolitic clay; and minor siliceous limestone. (Harriman and Camden are differentiated paleontologically.) Thickness 0 to 50 feet; Flat Gap Limestone - Thick-bedded, coarse-grained limestone, gray with red and brown grains. Thickness 0 to 13 feet; Ross Formation - Siliceous limestone; gray and variegated shale; and medium-grained glauconitic limestone. Thickness 0 to 75 feet.
Erwin Formation (Cambrian)
Erwin Formation - White, vitreous quartzite, massive, with interbeds of dark-green silty and sandy shale, minor siltstone, and very fine-grained sandstone. Thickness 1,000 to 1,500 feet.
Fentress Formation (Pennsylvanian)
Fentress Formation - Mostly dark-gray to light-brown shale, with minor siltstone and sandstone. Wilder coal near middle. Laterally equivalent to entire Gizzard Group and all of Crab Orchard Mountains Group below Rockcastle Conglomerate. Thickness as much as 340 feet.
Fort Payne Formation (Mississippian)
Fort Payne Formation - Bedded chert, calcareous and dolomitic, somewhat crinoidal; and minor shale. Thin green shale (Maury) at base. Thickness about 300 feet.
Fort Payne Formation (Mississippian)
Fort Payne Formation - Bedded chert, calcareous and dolomitic, somewhat crinoidal; and minor shale. Thin green shale (Maury) at base. Average thickness about 200 feet.
Fort Payne Formation and Chattanooga Shale (Mississippian)
Fort Payne Formation - Bedded chert and calcereous and dolomitic silicastone; minor coarse-grained limestone and shale. Thin green shale (Maury) at base. Thickness about 200 feet. Chattanooga Shale - Black carbonaceous shale, fissile. Thickness 0 to 70 feet.
Fort Payne Formation and Chattanooga Shale (Mississippian)
Fort Payne Formation - Bedded chert; calcareous and dolomitic silicastone; minor limestone and shale; scattered lenses of crinoidal limestone. Thin green shale (Maury) at base. Average thickness about 250 feet (475 in Wells Creek area); and Chattanooga Shale - Black carbonaceous shale, fissile. Thickness 0 to 70 feet; average about 20 feet. (Mapped as MDc on East-Central and East sheets)
Fort Payne Formation and Chattanooga Shale (Mississippian)
Fort Payne Formation - Calcareous and dolomitic silicastone; contains bedded chert, cherty limestone, and shale; scattered crinoidal limestone lenses. Thin green shale (Maury) at base. Thickness 100 to 275 feet.; and Chattanooga Shale - Black carbonaceous shale, fissile. Thickness 20 to 30 feet in most areas. (Mapped as MDc in Flynn Creek structure, where it is about 200 feet thick.) (Also mapped as MDc on the East Sheet)
Gizzard Group, including Signal Point Shale, Warren Point Sandstone, and Raccoon Mountain Formation (Pennsylvanian)
Gizzard Group - Shale, siltstone, sandstone, and conglomerate; from base of Sewannee Conglomerate to top of Mississippian. Thickness 0 to 520 feet, including Signal Point Shale - Mostly dark-gray to light-brown shale, with minor siltstone. Wilder coal near top. Thickness 0 to 180 feet, average about 60 feet; Warren Point Sandstone - Sandstone and conglomeratic sandstone, gray to brown, fine- to medium-grained, locally interbedded with shale containing coal. Thickness 0 to 300 feet, thins from southeast to northwest, average thickness about 100 feet; Raccoon Mountain Formation - Shale, siltstone, and sandstone. Bon Air coal near top; White Oak and Sale Creek coals near base. Thickness 0 to 260 feet.
Gizzard Group including Warren Point Sandstone and Raccoon Mountain Formation (Pennsylvanian)
Gizzard Group - Sandstone, conglomeratic sandstone, siltstone, shale, and minor coal. Thickness 100 to 200 feet. Includes Warren Point Sandstone - Gray to brown sandstone and minor conglomeratic sandstone. Thickness 60 to 160 feet; Raccoon Mountain Formation - Siltstone, sandstone, shale, and minor coal. Thickness 0 to 65 feet.
Grainger Formation (Mississippian)
Grainger Formation - Gray to green shale with siltstone and fine-grained glauconitic sandstone; in some areas quartz-pebble conglomerate. Thickness about 1,200 feet.
Grainger Formation (Mississippian)
Grainger Formation - Gray to green shale with siltstone and fine-grained glauconitic sandstone; in some areas quartz-pebble conglomerate. Thickness 500 to 1,000 feet.
Graves Gap Formation (Pennsylvanian)
Graves Gap Formation - Shale, sandstone, siltstone, and coal; from Windrock coal to top of Pioneer Sandstone. Thickness 275 to 385 feet.
Graves Gap Formation (Pennsylvanian)
Graves Gap Formation - Shale, sandstone, siltstone, and coal; from Windrock coal to top of Pioneer Sandstone. Thickness 200 to 350 feet.
Greasy Cove Formation and Grainger Formation (Mississippian)
Greasy Cove Formation - Gray, argillaceous limestone, calcareous shale, siltstone, and fine-grained sandstone. Equivalent to Newman Limestone. Maximum preserved thickness about 400 feet; and Grainger Formation - Gray to green shale with siltstone and fine-grained glauconitic sandstone; in some areas quartz-pebble conglomerate. Thickness about 1,200 feet.
Greasy Cove Formation, includes Grainger Formation (Mississippian)
Greasy Cove Formation, includes Grainger Formation- Gray argillaceous limestone, calcareous shale, siltstone, and fine-grained sandstone. Equivalent to Newman Limestone. Maximum preserved thickness about 400 feet.
Hampton Formation (Cambrian)
Hampton Formation - Dark greenish-gray, silty and sandy, micaceous shale; numerous layers of medium-grained, feldspathic, thinly bedded sandstone. Thickness 500 to 2,000 feet.
Hesse Sandstone (Cambrian)
Hesse Sandstone - White, vitreous quartzite, medium- to coarse-grained, occurs in massive ledges; Helenmode Member at top is gray to greenish sandstone and shale. Thickness about 600 feet.
Holston Formation (Ordovician)
Holston Formation - Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many areas upper part is sandy, crossbedded ferruginous limestone and brown to greenish calcareous shale. Thickness 200 to 600 feet.
Holston Formation (Ordovician)
Holston Formation - Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many areas upper part is sandy, crossbedded ferruginous limestone and brown to greenish calcareous shale. Thickness 200 to 600 feet.
Indian Bluff Formation (Pennsylvanian)
Indian Bluff Formation - Shale, sandstone, siltstone, and thin coal beds; from Pioneer Sandstone Member to Jellico coal. Thickness 150 to 250 feet.
Indian Bluff Formation (Pennsylvanian)
Indian Bluff Formation - Shale, sandstone, siltstone, and thin coal beds; from Pioneer Sandstone Member to Jellico coal. Thickness 150 to 415 feet.
Juniata Formation (Ordovician)
Juniata Formation - Maroon, claystone, siltstone, and shale; uniformly bedded; some faint greenish mottling; less calcareous than Sequatchie Formation. Thickness about 300 feet.
Laurel Limestone, Osgood Formation, and Brassfield Formation (Silurian)
Laurel Limestone - Dolomitic limestone, mottled yellowish-gray to yellowish-green, fine-grained. Thickness 0 to 10 feet. (Present only in Macon County); Osgood Formation - Grayish-green shale. Thickness 0 to 10 feet. (Present only in Macon County.); and Brassfield Formation - Olive-gray, fine-grained cherty limestone to the north, merging into olive-gray calcareous shale to the south. Thickness 60 to 130 feet. (Present only in Sequatchie Valley.)
Lebanon Limestone (Ordovician)
Lebanon Limestone - Thin-bedded limestone, gray to yellowish-brown, slightly dolomitic, with thin calcareous shale partings. Thickness about 100 feet.
Martinsburg Shale, including Reedsville Shale and Unnamed Limestone Unit (Ordovician)
Martinsburg Shale - Bluish-gray, calcareous clay shale, weathers yellowish-brown; with thin beds of nodular gray, fossiliferous limestone; thin layers of metabentonite near base. Thickness about 1,000 feet. Incluldes Reedsville Shale - Greenish-gray calcareous shale. Thickness 200 to 400 feet. and Unnamed Limestone Unit - Medium-grained, fossiliferous, gray limestone, shaly in part. Thickness as much as 600 feet.
Maryville Limestone, Rogersville Shale, Rutledge Limestone (Cambrian)
Maryville Limestone - Gray, ribboned (silt and dolomite), fine-grained, evenly bedded limestone; intraformational conglomerate and oolitic layers common; clay shale and light-gray dolomite locally. Thickness 300 to 800 feet; Rogersville Shale - Light-green, fissile clay shale; in places limestone (Craig Member) in upper part. Commonly 25 to 80 feet thick; maximum thickness 250 feet; Rutledge Limestone - Medium- to dark-gray, ribboned (silt and dolomite), medium-grained, well-bedded limestone; locally dark-gray, coarse-grained, medium-bedded dolomite in upper part. Thickness 100 to 500 feet.
Maryville, Rogersville, and Rutledge Formations (Cambrian)
Maryville, Rogersville, and Rutledge Formations - Maryville and Rutledge are gray limestone, in part oolitic, with gray dolomite locally. Rogersville is green clay shale. Thickness 400 to 1,000 feet.
Maynardville Limestone, Nolichucky Shale, and Honaker Dolomite (Cambrian)
Maynardville Limestone - Thick-bedded, bluish-gray, ribboned (silt and dolomite) nodular limestone; light-gray, fine-grained, laminated to thinly bedded, noncherty dolomite in upper part. Thickness 150 to 400 feet; Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly oolitic, shaly limestone lenses; locally stromatolitic limestone layers; thin, blocky siltstone near middle. Thickness 100 feet in the east to 900 feet in the west; Honaker Dolomite - Dark-gray, medium-bedded dolomite with minor dark limestone beds; locally cherty; cryptozoans abundant in places. Thickness about 1,500 feet.
Maynardville Limestone, Nolichucky Shale, Honaker Dolomite, Maryville Limestone, Rogersville Shale, Rutledge Limestone, Pumpkin Valley Shale (Cambrian)
Maynardville Limestone - Thick-bedded, bluish-gray, ribboned (silt and dolomite) nodular limestone; light-gray, fine-grained, laminated to thinly bedded, noncherty dolomite in upper part. Thickness 150 to 400 feet; Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly oolitic, shaly limestone lenses; locally stromatolitic limestone layers; thin, blocky siltstone near middle. Thickness 100 feet in the east to 900 feet in the west; Honaker Dolomite - Dark-gray, medium-bedded dolomite with minor dark limestone beds; locally cherty; cryptozoans abundant in places. Thickness about 1,500 feet; Maryville Limestone - Gray, ribboned (silt and dolomite), fine-grained, evenly bedded limestone; intraformational conglomerate and oolitic layers common; clay shale and light-gray dolomite locally. Thickness 300 to 800 feet; Rogersville Shale - Light-green, fissile clay shale; in places limestone (Craig Member) in upper part. Commonly 25 to 80 feet thick; maximum thickness 250 feet; Rutledge Limestone - Medium- to dark-gray, ribboned (silt and dolomite), medium-grained, well-bedded limestone; locally dark-gray, coarse-grained, medium-bedded dolomite in upper part. Thickness 100 to 500 feet; Pumpkin Valley Shale - Dull-brown to maroon shale with numerous interbeds of thin, blocky, and sandy siltstone. Thickness 100 to 600 feet.
Middle and Lower Parts of Chickamauga Group, including Mocassin Formation, Bays Formation, Sevier Shale, Ottosee Shale, Holston Formation, Lenoir Limestone and Athens Shale (Ordovician)
Middle and Lower Parts of Chickamauga Group - A sequence of about 1,400 feet of limestone in the northeast, which thickens and becomes more clastic to the southeast and is divided into the formations shown at right. Maximum thickness about 8,000 feet. Includes Mocassin Formation - Maroon calcareous shale, siltstone, and limestone; thin metabentonite layers in upper part; mud cracks, ripple marks common. Thickness 800 to 1,000 feet; (Ob) Bays Formation - Maroon claystone and siltstone, commonly mottled greenish, evenly bedded; to northeast, light- gray to white, thick-bedded sandstone; metabentonite in upper part. Maximum thickness 1,000 feet. (Osv) Sevier Shale - Calcareous, bluish-gray shale, weathers yellowish-brown; with thin gray limestone layers; sandstone, siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000 feet; (Oo) - Ottosee Shale - Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet; (Oh) - Holston Formation - Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many areas upper part is sandy, crossbedded ferruginous limestone and brown to greenish calcareous shale. Thickness 200 to 600 feet; (Ol) Lenoir Limestone - Nodular, argillaceous, gray limestone; in places basal sedimentary breccia, conglomerate, quartz sand; Mosheim Limestone Member (dense, light- to medium-gray limestone) near base. Thickness 25 to 500 feet; (Oa) Athens Shale - Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of shaly limestone near base. Maximum thickness 1,500 feet.
Middle and Lower parts of Chickamauga Group, including Moccassin Formation, Bays Formation, Sevier Shale, Ottosee Shale, Holston Formation, Lenoir Limestone, and Athens Shale (Ordovician)
Middle and Lower Parts of Chickamauga Group - A sequence of about 1,400 feet of limestone in the northwest part of Valley and Ridge, which thickens and becomes more clastic to the southeast and is divided into the formations shown at right. Maximum thickness about 7,000 feet. Includes Moccasin Formation - Maroon calcareous shale, siltstone, and limestone; thin metabentonite layers in upper part; mud cracks, ripple marks common. Thickness 800 to 1,000 feet;. (Ob) Bays Formation - Maroon, well-jointed claystone and siltstone, commonly mottled greenish, evenly bedded; light- gray sandstone beds and metabentonite in upper part. Maximum thickness 1,000 feet; (Osv) Sevier Shale - Calcareous, bluish-gray shale, weathers yellowish-brown; with thin, gray limestone layers; sandstone, siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000 feet; (Oo) Ottosee Shale - Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet; (Oh) Holston Formation - Pink, gray, and red coarsely crystalline limestone (Holston Marble); in many areas upper part is sandy, crossbedded ferruginous limestone and brown to greenish calcareous shale. Thickness 200 to 600 feet; (Ol) Lenoir Limestone - Nodular, argillaceous, gray limestone; in places basal sedimentary breccia, conglomerate, quartz sand; Mosheim Limestone Member (dense, light- to medium-gray limestone) near base. Thickness 25 to 500 feet; (Oa) Athens Shale - Medium- to dark-gray, calcareous, graptolitic shale; calcareous gray sandstone, siltstone, and locally fine-pebble quartz conglomerate; nodules of shaly limestone near base. Maximum thickness 1,500 feet.
Mississippian, Silurian, Devonian, and Ordovician Formations - containing all or portions of the Newman, Fort Payne, Chattanooga, Rockwood, and Sequatchie formations. (Mississippian to Ordovician)
Mississippian, Silurian, Devonian, and Ordovician Formations - Structurally complex area containing all or portions of the Newman, Fort Payne, Chattanooga, Rockwood, and Sequatchie formations.
Murray Shale (Cambrian)
Murray Shale - Shale, silty, sandy, dull-green to brown, micaceous. Thickness about 500 feet.
Nashville Group; Bigby-Cannon Limestone and Hermitage Formation (Ordovician)
Nashville Group - Bigby-Cannon Limestone - Brownish-gray phosphatic calcarenite and light-gray to brownish-gray, cryptograined to medium- grained, even-bedded limestone. Thickness 50 to 125 feet; and Hermitage Formation - Thin-bedded to laminated, sandy and argillaceous limestone with shale; nodular shaly limestone; coquina; and phosphatic calcarenite. Thickness 50 to 100 feet.
Newman Limestone (Mississippian)
Newman Limestone - Gray limestone sequence near Cumberland Plateau and on Whiteoak Mountain. Shaly limestone, shale, siltstone, and sandstone on Chilhowee Mountain. Thickness about 700 feet.
Newman Limestone (Mississippian)
Newman Limestone - Gray limestone sequence near Cumberland Plateau; shaly and silty limestone with minor sandstone and shale in the area of Clinch Mountain. Thickness 600 to 3,000 feet.
Nichols Shale (Cambrian)
Chilhowee Group; Nichols Shale - Olive-gray to green, silty and sandy, micaceous shale and siltstone; local lenses of fine-grained feldspathic quartzite. Thickness about 700 feet.
Nichols Shale (Cambrian)
Nichols Shale - Olive-gray to green, silty and sandy, micaceous shale and siltstone; local lenses of fine-grained feldspathic quartzite. Thickness about 700 feet.
Nolichucky Shale (Cambrian)
Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly oolitic, shaly limestone lenses; locally stromatolitic limestone layers; thin, blocky siltstone near middle. Thickness 100 feet in the east to 900 feet in the west.
Nolichucky Shale (Cambrian)
Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly oolitic, shaly limestone lenses; locally stromatolitic limestone layers; thin, blocky siltstone near middle. Thickness 500 feet in the east to 900 feet in the west.
Nolichucky Shale, and Maryville, Rogersville, and Rutledge Formations, and Pumpkin Valley Shale (Cambrian)
(Cn) Nolichucky Shale - Pastel-colored (pink, greenish, olive), flaky clay shale; gray, commonly oolitic, shaly limestone lenses; locally stromatolitic limestone layers; thin, blocky siltstone near middle. Thickness 500 feet in the east to 900 feet in the west.; (Cmr) Maryville, Rogersville, and Rutledge Formations - Maryvile and Rutledge are gray limestone, in part oolitic, with gray dolomite locally. Rogersville is green clay shale. Thickness 400 to 1,000 feet. Pumpkin Valley Shale - Dull-brown to maroon shale with numerous interbeds of thin, blocky, sandy siltstone. Thickness 100 to 600 feet.
Ocoee Supergroup, including Walden Creek Group, (including Sandsuck Formation, Wilhite Formation, Shields Formation, Licklog Formation), Cades Sandstone, and Rich Butt Sandstone (Precambrian)
Ocoee Supergroup - Terrigenous clastic sedimentary rocks, for the most part poorly sorted and coarse. The groups are subdivided into formations only in the region of the Great Smoky Mountains. Thickness as much as 50,000 feet. Includes Walden Creek Group - The formations, other than the Sandsuck, have been mapped only in the region of the Great Smoky Mountains. Thickness about 8,000 feet; Sandsuck Formation - Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet; Wilhite Formation - Gray to green siltstone and slate with interbeds of pebble conglomerate, sandstone, and quartzite. Thickness about 4,000 feet; Shields Formation - Massive conglomerate, sandstone, argillaceous slate; conglomerate (pebbles of various rock types) characteristic. Thickness about 1,500 feet; Licklog Formation - Feldspathic sandstone, greenish phyllite, and bluish-gray slate. Thickness about 1,500 feet; and the Cades Sandstone - Gray, well-bedded, fine- to medium-grained feldspathic metasandstone, with interbeds of dark slate and metasiltstone; precise stratigraphic position unknown. Thickness about 1,500 feet; and Rich Butt Sandstone - Gray, massive beds of feldspathic, fine- to medium-grained sandstone, with interbeds of dark slate and arkosic conglomerate; exact stratigraphic position unknown. Thickness about 1,500 feet.
Ordovician formations, including Mannie Shale, Fernvale Limestone, Hermitage Formation, and Carters, Lebanon, Ridley, Pierce, and Murfreesboro Limestones (Ordovician)
Ordovician formations - including Mannie Shale - Shale with thin beds of argillaceous limestone. Thickness 0 to 20 feet; Fernvale Limestone - Thick-bedded, coarse-grained, gray limestone with varicolored grains. Thickness 0 to 30 feet; Hermitage Formation - Gray shale and thin-bedded to laminated, sandy and argillaceous limestone. About 200 to 300 feet thick in Wells Creek Basin; only about 80 feet exposed in Western Valley; and the Carters, Lebanon, Ridley, Pierce, and Murfreesboro Limestones - Thin- to thick-bedded, cryptograined to coarse-grained, yellowish-brown to olive-gray limestones. Thickness about 1,000 feet. (Not exposed in Western Valley.)
Ordovician Formations including Richmond Group (Mannie Shale, Fernvale Limestone), and Nashville Group (Hermitage Formation) (Ordovician)
Ordovician Formations - Richmond Group (including Mannie Shale - Shale with thin beds of argillaceous limestone. Thickness 0 to 20 feet and Fernvale Limestone - Thick-bedded, coarse-grained limestone with vari-colored grains. Thickness 0 to 20 feet). and Nashville Group (including Hermitage Formation - Gray shale and thin-bedded to laminated, sandy and argillaceous limestone. Maximum exposed thickness 80 feet.)
Ottosee Shale (Ordovician)
Ottosee Shale - Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet.
Ottosee Shale (Ordovician)
Ottosee Shale - Bluish-gray calcareous shale, weathers yellow; with reef lenses of coarsely crystalline reddish fossiliferous limestone ("marble"). Thickness about 1,000 feet.
Pennington Formation (Mississippian)
Pennington Formation - Reddish and greenish shale and siltstone; fine-grained dolomite; and minor fragmental and oolitic limestone. Thickness 240 to 360 feet.
Pennington Formation (Mississippian)
Pennington Formation - Highly variegated clay shale, distinctive; contains siltstone and locally gray, fine-grained sandstone. Thickness 400 to 700 feet.
Pennington Formation (Mississippian)
Pennington Formation - Highly variegated clay shale distinctive; contains siltstone beds and locally gray, fine-grained sandstone. Thickness 300 to 500 feet near Cumberland Plateau; maximum of about 1,250 feet to the east.
Pennington Formation (Mississippian)
Pennington Formation - Reddish and greenish shale and siltstone; fine-grained dolomite; dark-gray limestone; and thin-bedded sandstone. Persistent dolomite bed at base. Thickness 150 to 400 feet.
Pumpkin Valley Shale (Cambrian)
Pumpkin Valley Shale - Dull-brown to maroon shale with numerous interbeds of thin, blocky, and sandy siltstone. Thickness 100 to 600 feet.
Redoak Mountain Formation (Pennsylvanian)
Redoak Mountain Formation - Shale, sandstone, silicastone, and several important coals; from Pewee coal to Windrock coal. Thickness 340 to 420 feet.
Redoak Mountain Formation (Pennsylvanian)
Redoak Mountain Formation - Shale, sandstone, siltstone, and several important coals; from Pewee coal to Windrock coal. Thickness 340 to 420 feet.
Ridley Limestone (Ordovician)
Ridley Limestone - Medium- to very thick-bedded, fine- to medium-grained, gray dolomitic limestone, with prominent greenish-gray calcareous shale and shaly limestone unit in middle. Thickness 200 to 275 feet.
Rockcastle Conglomerate (Pennsylvanian)
Rockcastle Conglomerate - Conglomeratic sandstone and sandstone, gray to brown, fine- to coarse-grained. Thin coal-bearing shale locally present near middle. Thickness 150 to 220 feet.
Rockwood Formation (Silurian)
Rockwood Formation - Brown to maroon shale, thin gray siltstone and sandstone, and thin lenticular layers of oolitic and fossiliferous red hematite. Thickness 200 to 800 feet.
Rockwood Formation (Silurian)
Rockwood Formation - Brown to maroon shale, thin gray siltstone and sandstone, and thin lenticular layers of oolitic and fossiliferous red hematite. Thickness 350 to 550 feet.
Rockwood Formation and Clinch Sandstone (Silurian)
Rockwood Formation - Brown to maroon shale, thin gray siltstone and sandstone, and thin lenticular layers of oolitic and fossiliferous red hematite. Thickness 200 to 800 feet; and Clinch Sandstone - Clean, white, well-sorted sandstone; locally gray siltstone and shale. Combined Rockwood and Clinch thicknesses about 700 feet.
Rockwood Formation and Clinch Sandstone (Silurian)
Rockwood Formation - Brown to maroon shale, thin gray siltstone and sandstone, and thin lenticular layers of oolitic and fossiliferous red hematite. Thickness 350 to 550 feet; Clinch Sandstone - Clean, white, well-sorted sandstone; locally gray siltstone and shale. Average thickness about 600 feet.
Rogersville Shale (Cambrian)
Rogersville Shale - Light-green, fissile clay shale; in places limestone (Craig Member) in upper part. Commonly 25 to 80 feet thick; maximum thickness 250 feet.
Rome Formation (Cambrian)
Rome Foundation - Variegated (red, green, yellow) shale and siltstone; gray, fine-grained sandstone in middle and west part of Valley and Ridge; abundant limestone and dolomite in east. Thickness about 2,000 feet.
Rome Formation (Cambrian)
Rome Formation - Variegated (red, green, yellow) shale and siltstone with beds of gray, fine-grained sandstone. Maximum exposed thickness 1,500 feet.
Sandsuck Formation (Precambrian)
Sandsuck Formation - Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet.
Sequatchie Formation (Ordovician)
Sequatchie Formation - Maroon and gray shaly limestone, mottled greenish; with interbeds of calcareous, olive to maroon shale and siltstone. Average thickness about 200 feet.
Sequatchie Formation (Ordovician)
Sequatchie Formation - Maroon and gray shaly limestone, mottled greenish; with interbeds of olive to maroon calcareous shale and siltstone. Thickness about 300 feet.
Sequatchie Formation, Leipers Formation, Inman Formation and Catheys Formation (Ordovician)
Sequatchie Formation - Greenish-gray calcareous shale, mudstone, and argillaceous limestone; dolomitic, laminated, and sandy. Thickness 0 to 165 feet; Leipers Formation - Nodular, shaly limestone and fine- to coarse-grained limestone. Thickness 0 to 150 feet; Inman Formation - Thin-bedded to laminated, fine-grained, greenish-gray limestone interbedded with red and green calcareous shale beds. Thickness 0 to 50 feet. (Present only in Sequatchie Valley.); and Catheys Formation - Nodular, shaly, thin- to medium-bedded limestone and fine- to coarse-grained limestone. Thickness 125 to 400 feet.
Sevier Shale (Ordovician)
Sevier Shale - Calcareous, bluish-gray shale, weathers yellowish-brown; with thin gray limestone layers; sandstone, siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000 feet.
Sevier Shale (Ordovician)
Sevier Shale - Calcareous, bluish-gray shale, weathers yellowish-brown; with thin, gray limestone layers; sandstone, siltstone, and locally conglomerate to the east. Thickness 2,000 to 7,000 feet.
Shady Dolomite (Cambrian)
Shady Dolomite - Light-gray dolomite and thinly bedded limestone with much shaly gray limestone and calcareous gray shale. Thickness about 1,000 feet.
Silurian Formations, including Decatur Limestone, Brownsport Group (Lobelville Formation, Bob Limestone, Beech River Formation), Wayne Group (Dixon Formation, Lego Formation, Waldron Shale, Laurel Limestone, Osgood Formation) and Brassfield Limestone (Silurian)
Silurian Formations - Characteristically light olive-gray to greenish-gray, with variable reddish-brown color in some areas. Individual formations are generally uniform in thickness, except where truncated by pre- Chattanooga erosion. Most formations are slightly thicker (than indicated) in Wells Creek Basin. Includes Decatur Limestone- Thick-bedded, medium- to coarse-grained limestone, gray with reddish-brown grains. Thickness 0 to 70 feet; Brownsport Group ( which includes Lobelville Formation - Shale with thin beds of limestone. Thickness 0 to 30 feet; Bob Limestone - Thick-bedded, medium-grained limestone, locally oolitic. Thickness 0 to 25 feet; and Beech River Formation - Shale with thin beds of limestone. Thickness 0 to 60 feet); Wayne Group (which includes Dixon Formation - Green and reddish-brown argillaceous limestone, shale, and mudstone. Thickness 0 to 40 feet; Lego Limestone - Even-bedded, olive-gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; Waldron Shale - Greenish-gray fossiliferous shale. Thickness 0 to 5 feet; Laurel Limestone - Even-bedded, olive-gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; Osgood Formation - Greenish- and reddish-gray shale and argillaceous limestone. Thickness 0 to 15 feet); and Brassfield Limestone - Thin-bedded cherty limestone, locally glauconitic. Thickness 0 to 50 feet; generally about 20 feet.
Silurian Formations, including Decatur Limestone, Brownsport Group (Lobelville Formation, Bob Limestone, Beech River Formation), Wayne Group (Dixon Formation, Lego Formation, Waldron Shale, Laurel Limestone, Osgood Formation) and Brassfield Limestone (Silurian)
Silurian Formations - A complete section of Silurian formations is not common because of pre-Chattanooga and/or pre- Cretaceous erosion. Where preserved, Silurian formations are remarkably uniform in thickness and are characteristically light olive-gray to greenish-gray with variable reddish-brown color in some area;. Decatur Limestone - Thick-bedded, medium- to coarse-grained limestone, gray with reddish-brown grains. Thickness 0 to 70 feet; Brownsport Group which includes 1) Lobelville Formation - Shale with thin beds of limestone. Thickness 0 to 40 feet; 2) Bob Limestone - Thick-bedded, medium-grained limestone, locally oolitic. Thickness 0 to 25 feet; and 3) Beech River Formation - Shale with thin beds of limestone. Thickness 0 to 60 feet; Wayne Group which includes: 1) Dixon Formation - Green and reddish-brown argillaceous limestone, shale, and mudstone. Thickness 0 to 40 feet; 2) Lego Limestone - Even-bedded, olive-gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; 3) Waldron Shale - Greenish-gray fossiliferous shale. Thickness 0 to 5 feet; 4) Laurel Limestone - Even-bedded, gray limestone with scattered reddish-brown grains. Thickness 0 to 30 feet; 5) Osgood Formation - Greenish- and reddish-gray shale and argillaceous limestone. Thickness 0 to 15 feet.; and Brassfield Limestone - Thin-bedded cherty limestone, locally glauconitic. Thickness 0 to 20 feet.
Slatestone Formation (Pennsylvanian)
Slatestone Formation - Shale, sandstone, siltstone, and several important coals; from Jellico coal to Poplar Creek coal. Thickness 500 to 650 feet.
Slatestone Formation (Pennsylvanian)
Slatestone Formation - Shale, sandstone, siltstone, and several important coals; from Jellico coal to Poplar Creek coal. Thickness 500 to 720 feet.
Sneedville Limestone (Devonian to Silurian)
Sneedville Limestone - Gray silty limestone and dolomite, minor shale, and fine-grained, greenish-gray sandstone; fossils locally abundant. Thickness 100 to 300 feet.
St. Genevieve Limestone (Mississippian)
St. Genevieve Limestone - Gray limestone, slightly oolitic and cherty, with some green shale and fine-grained sandstone. Maximum preserved thickness 70 feet. (In Western Highland Rim area only.)
St. Louis Limestone and Warsaw Limestone (Mississippian)
St. Louis Limestone - Fine-grained, brownish-gray limestone, dolomitic and cherty. Thickness 100 to 280 feet; and Warsaw Limestone - Coarse-grained, gray, crossbedded limestone; somewhat shaly in the northeast. Thickness 40 to 150 feet.
St. Louis Limestone and Warsaw Limestone (Mississippian)
St. Louis Limestone - Fine-grained, brownish-gray limestone, dolomitic and cherty. Thickness 80 to 160 feet.; and Warsaw Limestone - Mainly medium- to coarse-grained, gray limestone, crossbedded. Includes much calcareous sandstone and shale to the north. Thickness 100 to 130 feet.
Stones River Group; Lebanon Limestone (Ordovician)
Stones River Group; Lebanon Limestone - Thin-bedded, gray limestone with calcareous shale partings. Thickness 80 to 100 feet.
Stones River Group; Pierce Limestone and Murfreesboro Limestone (Ordovician)
Stones River Group; Pierce Limestone - Gray, thin-bedded limestone with shale partings. Thickness 25 feet; and Murfreesboro Limestone - Thick-bedded, dark-gray, fine-grained limestone, with mottlings of magnesian limestone; somewhat cherty in upper part. Maximum exposed thickness 70 feet.
Unicoi Formation (Cambrian)
Unicoi Formation - Sequence of gray feldspathic sandstone, arkose, conglomerate, graywacke, siltstone and shale; greenish amygdaloidal basalt flows near middle and base. Thickness 2,000 to 5,000 feet.
Vowell Mountain Formation (Pennsylvanian)
Vowell Mountain Formation - Shale, sandstone, siltstone, and coal; from Frozen Head Sandstone Member to Pewee coal. Thickness 230 to 375 feet.
Vowell Mountain Formation (Pennsylvanian)
Vowell Mountain Formation - Shale, sandstone, siltstone, and coal; from Frozen Head Sandstone Member to Pewee coal. Thickness 300 to 375 feet.
Walden Creek Group, including Sandsuck Formation, Wilhite Formation, Shields Formation, and Licklog Formation (Cambrian)
Walden Creek Group - The formations, other than the Sandsuck, are applicable mainly in the region of the Great Smoky Mountains. Thickness about 8,000 feet, Includes Sandsuck Formation - Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet; Wilhite Formation - Gray to green siltstone and slate with interbeds of pebble conglomerate, sandstone, and quartzite. Thickness about 4,000 feet; Shields Formation - Massive conglomerate, sandstone, argillaceous slate; conglomerate (pebbles of various rock types) characteristic. Thickness about 1,500 feet.; Licklog Formation - Feldspathic sandstone, greenish phyllite, and bluish-gray slate. Thickness about 1,500 feet.
Walden Creek Group, including Sandsuck Formation, Wilhite Formation, Shields Formation, and Licklog Formation (Precambrian)
The formations, other than the Sandsuck, have been mapped only in the region of the Great Smoky Mountains. Thickness about 8,000 feet. Includes Sandsuck Formation - Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet; Wilhite Formation - Gray to green siltstone and slate with interbeds of pebble conglomerate, sandstone, and quartzite. Thickness about 4,000 feet; Shields Formation - Massive conglomerate, sandstone, argillaceous slate; conglomerate (pebbles of various rock types) characteristic. Thickness about 1,500 feet; Licklog Formation - Feldspathic sandstone, greenish phyllite, and bluish-gray slate. Thickness about 1,500 feet.
Walden Creek Group; Sandsuck Formation (Precambrian)
Wladen Creek Group; Sandsuck Formation - Olive-green and gray, argillaceous, micaceous shale with coarse feldspathic sandstone and quartz- pebble conglomerate. Thickness about 2,000 feet.
Wells Creek Dolomite and Knox Group (Ordovician)
Wells Creek Dolomite and Knox Group - Yellowish-gray and light olive-gray dolomite, within partings of grayish-green shale, and pale- orange to yellowish-gray limestone; thin- to thick-bedded, micrograined to coarse-grained. Present only in Wells Creek Basin. Exposed thickness at least 600 feet. (Also mapped with Onc on East-Central Sheet)
Wells Creek Formation and Knox Group (above Copper Ridge Dolomite) (Ordovician)
Wells Creek Formation - Gray limestone and dolomite, with angular chert blocks and fragments; and minor shale, mottled red and green, calcareous. Thickness 0 to 50 feet. (Present only in Sequatchie Valley.); and Knox Group (above Copper Ridge Dolomite) - Gray, cherty dolomite and limestone, fine- to medium-grained. Maximum exposed thickness in Sequatchie Valley 600 feet. (Units in Onc are also mapped as OCk on the West-Central Sheet)

Texas

Admiral and Coleman Junction Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Admiral and Coleman Junction Formations, undivided
Alta Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Alta Formation
Barnett Formation, Chappel Limestone, Houy, Zesch, Bear Spring, and Stribling Formations, and Pillar Bluff Limestone, undivided (Phanerozoic | Paleozoic | Devonian Carboniferous Mississippian-Early Mississippian-Middle Mississippian-Late)
Barnett Formation, Chappel Limestone, Houy, Zesch, Bear Spring, and Stribling Formations, and Pillar Bluff Limestone, undivided
Bead Mountain Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Bead Mountain Formation
Benevides Formation and Finlay Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean])
Benevides Formation and Finlay Limestone, undivided
Bissett Conglomerate (Phanerozoic | Mesozoic | Cretaceous-Early)
Bissett Conglomerate
Bluff Mesa Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
Bluff Mesa Formation
Boracho and Finlay Limestones, undivided (Phanerozoic | Mesozoic | Cretaceous-Early)
Boracho and Finlay Limestones, undivided NOTE: This unit is represented within the map unit explanation of (Geol. Map of Texas, 1992, Bur. Econ. Geol.) but does not occur on the map and is NOT included in the spatial data.
Bouquillas Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Bouquillas Formation
Brushy Canyon Formation (Phanerozoic | Paleozoic | Permian [Guadalupe])
Brushy Canyon Formation
Buda Limestone and Del Rio Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Late)
Buda Limestone and Del Rio Clay, undivided
Buda Limestone and Eagle Mountain Sandstone, undivided (Phanerozoic | Mesozoic | Cretaceous-Late)
Buda Limestone and Eagle Mountain Sandstone, undivided
Buda Limestone and San Martine Member of Borache Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Late)
Buda Limestone and San Martine Member of Borache Limestone, undivided
Caballos Novaculite and Maravillas Chert, undivided (Phanerozoic | Paleozoic | Ordovician-Late Devonian Carboniferous Mississippian)
Caballos Novaculite and Maravillas Chert, undivided
Cathederal Mountain Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Cathederal Mountain Formation
Cedarton Shale and Adams Branch Limestone, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Cedarton Shale and Adams Branch Limestone, undivided
Cibolo Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Cibolo Formation
Cienequita Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle Pennsylvanian-Late)
Cienequita Formation
Cloud Chief Formation (Phanerozoic | Paleozoic | Permian [Guadalupe])
Cloud Chief Formation
Comanchean rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Early [Washita])
Comanchean rocks, undivided
Comanche Peak Limestone (Phanerozoic | Mesozoic | Cretaceous-Early [Albian])
Comanche Peak Limestone NOTE: This unit is represented within the map unit explanation of (Geol. Map of Texas, 1992, Bur. Econ. Geol.) but does not occur on the map and is NOT included in the spatial data.
Comanche Peak Limestone, Walnut Clay, and Antlers Sand, undivided (Phanerozoic | Mesozoic | Cretaceous-Early)
Comanche Peak Limestone, Walnut Clay, and Antlers Sand, undivided
Cow Creek Limestone, Hammett Shale, and Sycamore Sand, undivided (Phanerozoic | Mesozoic | Cretaceous-Early)
Cow Creek Limestone, Hammett Shale, and Sycamore Sand, undivided
Cretaceous rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Late)
Cretaceous rocks, undivided
Cutoff Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Cutoff Formation
Dakota and Purgatoir Formations, undivided (Phanerozoic | Mesozoic | Cretaceous-Early)
Dakota and Purgatoir Formations, undivided
Dakota Formation (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Late)
Dakota Formation
Dimple Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early)
Dimple Formation
Eagle Ford Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Eagle Ford Formation
Eagle Ford Formation and Woodbine Formations, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian])
Eagle Ford Formation and Woodbine Formations, undivided
Elm Creek Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Elm Creek Formation
Escondido Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian])
Escondido Formation
Espy Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
Espy Formation
Etholen Conglomerate (Phanerozoic | Mesozoic | Cretaceous-Early)
Etholen Conglomerate
Gatuna Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle(?))
Gatuna Formation
Grape Creek Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Grape Creek Formation
Grindstone Creek Formation, expanded (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines])
Grindstone Creek Formation, expanded
Gulfian rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Late)
Gulfian rocks, undivided
Helms Shale, Rancheria Formation, Las Cruces Limestone, Percha Shale, and Canutillo Formations, undivided (Phanerozoic | Paleozoic | Devonian Carboniferous Mississippian-Late [Chesteran])
Helms Shale, Rancheria Formation, Las Cruces Limestone, Percha Shale, and Canutillo Formations, undivided
Hensell Sand (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean)
Hensell Sand
Home Creek Limestone and Colony Creek Shale, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Home Creek Limestone and Colony Creek Shale, undivided
Hueco Limestone (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Hueco Limestone
Jagger Bend and Valera Formations, undivided (Phanerozoic | Paleozoic | Permian [Leonard])
Jagger Bend and Valera Formations, undivided
Lazy Bend Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines])
Lazy Bend Formation
Lenox Hills and Neal Ranch Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Lenox Hills and Neal Ranch Formations, undivided
Llanoria Quartzite (preCambrian-Proterozoic [Grenville])
Llanoria Quartzite
Loma Plata Formation (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean])
Loma Plata Formation
Lueders Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Lueders Formation
Magdalena Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian (?))
Magdalena Formation
Malone Formation (Phanerozoic | Mesozoic | Jurassic-Late)
Malone Formation
Marble Falls Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Morrow])
Marble Falls Limestone
McKnight Formation (Phanerozoic | Mesozoic | Cretaceous-Early )
McKnight Formation
Mineral Wells Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Mineral Wells Formation
Mingus Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines])
Mingus Formation
Mississippi, Devonian, and Ordovician rocks, undivided (Phanerozoic | Paleozoic | Ordovician Devonian Carboniferous Mississippian)
Mississippi, Devonian, and Ordovician rocks, undivided
Morrison Formation (Phanerozoic | Mesozoic | Jurassic-Late)
Morrison Formation
Ojinaga Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Ojinaga Formation
Ordovician rocks, undivided (Phanerozoic | Paleozoic| Ordovician)
Ordovician rocks, undivided
Paleozoic rocks, undivided (Phanerozoic | Paleozoic)
Paleozoic rocks, undivided
Palo Pinto Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Palo Pinto Formation
Permian rocks, undivided (Phanerozoic | Paleozoic | Permian)
Permian rocks, undivided
Quartermaster Formation (Phanerozoic | Paleozoic | Permian [Guadalupe])
Quartermaster Formation
Ranger Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Ranger Limestone
Ranger Limestone and Placid Creek Shale, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Ranger Limestone and Placid Creek Shale, undivided
Riley Formation showing Lion Mountain Sandstone and Cap Mountain Limestone Members, undivided (Phanerozoic | Paleozoic | Cambrian-Middle)
Riley Formation showing Lion Mountain Sandstone and Cap Mountain Limestone Members, undivided
Santa Anna Branch Shale (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Santa Anna Branch Shale
Santa Anna Branch Shale and Sedwick and Moran Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Santa Anna Branch Shale and Sedwick and Moran Formations, undivided
Santa Elena Limestone, Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early)
Santa Elena Limestone, Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided
Skinner Ranch and Hess Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Skinner Ranch and Hess Formations, undivided
Smithwick Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atoka])
Smithwick Formation
Strawn Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atoka Des Moines])
Strawn Group
Sue Peaks Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
Sue Peaks Formation
Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early)
Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided
Talpa Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Talpa Formation
Thrifty and Graham Formations, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgil])
Thrifty and Graham Formations, undivided
Torcer Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
Torcer Formation
undivided part Fredericksberg Group (Phanerozoic | Mesozoic | Cretaceous-Early)
undivided part Fredericksberg Group
undivided parts of Washita and Fredericksberg Groups (Phanerozoic | Mesozoic | Cretaceous-Early)
undivided parts of Washita and Fredericksberg Groups
unnamed Pennsylvanian rocks (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian)
unnamed Pennsylvanian rocks
upper Cretaceous rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Late)
upper Cretaceous rocks, undivided
Waggoner Ranch Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Waggoner Ranch Formation
Walnut Clay (Phanerozoic | Mesozoic | Cretaceous-Early)
Walnut Clay
Whitehorse Group and Blaine Formation, undivided (Phanerozoic | Paleozoic | Permian [Guadalupe])
Whitehorse Group and Blaine Formation, undivided
Whitehorse Group, undivided (Phanerozoic | Paleozoic | Permian [Guadalupe])
Whitehorse Group, undivided
Winchell Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Winchell Limestone
Wolf Mountain Shale (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri])
Wolf Mountain Shale
Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian])
Woodbine Formation
Word Formation (Phanerozoic | Paleozoic | Permian [Guadalupe])
Word Formation
Yates Formation (Phanerozoic | Paleozoic | Permian [Guadalupe])
Yates Formation
Yearwood Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
Yearwood Formation

Utah

Cambrian quartzite in Uinta Mountains-Uinta Basin area (Early to Middle Cambrian)
Cretaceous (1) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Early Cretaceous)
Cretaceous (1) sedimentary rocks in southeastern Utah (Cretaceous)
Cretaceous (1) sedimentary rocks in southwestern Utah (Late Cretaceous)
Cretaceous (1) sedimentary rocks in Uinta Mountains-Uinta Basin region (Cretaceous)
Cretaceous (2) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Late Cretaceous)
Cretaceous (2) sedimentary rocks in southeastern Utah (Late Cretaceous)
Cretaceous (2) sedimentary rocks in southwestern Utah (Late Cretaceous)
Cretaceous (2) sedimentary rocks in Uinta Mountains-Uinta Basin region (Late Cretaceous)
Cretaceous (3) sedimentary rocks in southeastern Utah (Late Cretaceous)
Cretaceous (3) sedimentary rocks in Uinta Mountains-Uinta Basin region (Late Cretaceous)
Devonian sedimentary rocks in southewestern Utah (Devonian)
Jurassic (2) sedimentary rocks in southeastern Utah (Late Jurassic)
Jurassic (2) sedimentary rocks in Uinta Mountains-Uinta Basin region (Late Jurassic)
Middle Cambrian shale and carbonate rocks in central Utah (Middle Cambrian)
Middle Cambrian shale and carbonate rocks in Logan-Huntsville Allochthon (Middle Cambrian)
Middle Cambrian shale and carbonate rocks in Salt Lake City-Coalville-Randolph region (Middle Cambrian)
Middle Cambrian shale and carbonate rocks in western Utah (Middle Cambrian)
Mississippian (2) sedimentary rocks in Uinta Mountains-Uinta Basin region (Mississippian)
Mississippian (2) sedimentary rocks in western Utah (Mississippian)
Mississippian (3) sedimentary rocks in central Utah (Mississippian)
Mississippian (3) sedimentary rocks in Logan-Huntsville Allochthon (Mississippian)
Mississippian (3) sedimentary rocks in northwestern Utah (Mississippian)
Mississippian (3) sedimentary rocks in Uinta Mountains-Uinta Basin region (Mississippian)
Permian (2) sedimentary rocks in Logan-Huntsville Allochthon (Permian)
Permian (2) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Permian)
Tertiary (2) sedimentary rocks in central Utah (Eocene)
Tertiary (2) sedimentary rocks in southwestern Utah (Eocene)
Tertiary (2) sedimentary rocks in Uinta Mountains-Uinta Basin region (Eocene)
Triassic (2) sedimentary rocks in Logan-Huntsville Allochthon (Middle to Late Triassic)
Triassic (2) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Middle to Late Triassic)
Triassic (2) sedimentary rocks in Uinta Mountains-Uinta Basin region (Late Triassic)
Triassic (2) sedimentary rocks in western Utah (Late Triassic)
Upper Cambrian carbonate rocks in central Utah (Middle Cambrian to Early Ordovician)
Upper Cambrian carbonate rocks in western Utah (Middle Cambrian to Early Ordovician)
Younger Precambrian metamorphic rocks in Uinta Mountains-Uinta Basin region (Proterozoic Y)

Virginia

Bluefield Formation (Mississippian)
Bluefield Formation - Calcareous shale and limestone.
Brallier Formation (Devonian)
Brallier Formation - Micaceous shale, siltstone, and sandstone.
Chemung Formation (redefined as Foreknobs Formation) (Devonian)
Chemung Formation - Shale and sandstone with a few thin, quartz-pebble conglomerates and red-beds.
Conasauga Shale (Cambrian)
Conasauga Shale - Shale with minor limestone and sandstone.
Elbrook Formation (Cambrian)
Elbrook Formation - Dolomite, shale, and minor limestone.
Erwin and Hampton Formations (Cambrian)
Erwin and Hampton Formations - Sandstone, quartzite, and shale.
Greenbrier Limestone (Mississippian)
Greenbrier Limestone - Limestone, in part cherty, fossiliferous; shale.
Hampshire Formation (Devonian)
Hampshire Formation - Dusky-red to grayish-red shale, mudrock, and sandstone.
Hancock, Rose Hill, and Clinch Formations (Silurian)
Hancock, Rose Hill, and Clinch Formations - Limestone and dolomite; dusky-red and green shale and sandstone; and sandstone, shale and conglomerate.
Hardy Creek Limestone through Dot Limestone (Ordovician)
Hardy Creek Limestone through Dot Limestone - Limestone, in part cherty; and calcareous shale. Includes Hardy Creek, Ben Hur, Woodway, Hurricane Bridge, Martin Creek, Rob Camp, Poteet, and Dot Limestones.
Harlan Sandstone (Pennsylvanian)
Harlan Sandstone - Sandstone, siltstone, shale, and coal.
Juniata, Oswego, Martinsburg (Reedsville and Dolly Ridge), and Eggleston Formations (Ordovician)
Juniata, Oswego, Martinsburg (Reedsville and Dolly Ridge), and Eggleston Formations - Dusky-red shale and mudstone and sandstone; graywacke; shale and sandstone; and limestone.
Juniata, Reedsville, Trenton, and Eggleston Formations (Ordovician)
Juniata, Reedsville, Trenton, and Eggleston Formations - Dusky-red shale and mudstone and sandstone; shale and limestone. Note: one area in southeastern Bland County has landslides with intact stratigraphic units.
Kanawha Formation (Pennsylvanian)
Kanawha Formation - Sandstone, siltstone, shale, and coal.
Keefer, Rose Hill, and Tuscarora Formations (Silurian)
Keefer, Rose Hill, and Tuscarora Formations - Quartzarenite, dusky-red shale, and sandstone, Some landslides with intact stratigraphic units in Craig County area..
Knobs Formation, Paperville Shale, Lenoir and Mosheim Limestone (Ordovician)
Knobs Formation, Paperville Shale, Lenoir and Mosheim Limestone - Sandstone, conglomerate, siltstone; black, fissile shale; and limestone, in part cherty.
Lee Formation (Pennsylvanian - Mississippian)
Lee Formation - Quartzarenite, sandstone, conglomerate, shale, siltstone, and coal.
Lee Formation (Pennsylvanian)
Lee Formation - Quartzarenite, sandstone, conglomerate, shale, siltstone, and coal.
Lower Devonian and Silurian Formations Undivided (Silurian-Devonian)
Lower Devonian and Silurian Formations Undivided - Some landslides with intact stratigraphic units in Craig County area. Includes: Dsu, Skrt, Sm. (Shrc?)
Lower Devonian, Silurian and Upper Ordovician Formations Undivided (Ordovician-Devonian)
Lower Devonian, Silurian and Upper Ordovician Formations Undivided - Some landslides with intact stratigraphic units in Giles County. Includes: Skrt, Sm, Oun, Ous, Ou, Om. (Shrc, Okpl?)
Maccrady Shale (Mississippian)
Maccrady Shale - Dusky-red and green shale and mudstone; and evaporite deposits.
Maccrady Shale and Price Formation (Mississippian)
Maccrady Shale and Price Formation - Includes: Maccrady Shale: Dusky-red and green shale and mudstone; and evaporite deposits. Price Formation: Sandstone, conglomeratic sandstone, and shale with carbonaceous partings and impure coal beds.
Mahantango Formation (Devonian)
Mahantango Formation - Sandstone with interbedded shale, fossiliferous
Marcellus Shale and Needmore Formation (Devonian)
Marcellus Shale and Needmore Formation - Black, fissile shale; gray, non-fissile shale; Tioga metabentonite at top of Needmore
Martinsburg and Oranda Formations (Ordovician)
Martinsburg and Oranda Formations - Shale, sandstone, siltstone, and limestone.
Millboro Shale and Needmore Formation (Devonian)
Millboro Shale and Needmore Formation - Black, fissile shale; gray calcareous shale; Tioga metabentonite at top of Needmore.
Mississippian Formations Undivided (Mississippian)
Mississippian Formations Undivided - Includes Pennington Group, Bluefield Formation, Greenbrier Limestone, Maccrady Shale and Price Formation; Includes Newman Limestone, Fort Payne Chert, and Grainger Formation in western Lee County
Moccasin or Bays Formation through Blackford Formation (Ordovician)
Moccasin or Bays Formation through Blackford Formation - Dusky-red shale and mudstone; sandstone; limestone, in part cherty; and calcareous shale.
Mount Rogers Formation - Conglomerate, graywacke, laminated siltstone, and shale. (Proterozoic Z)
Mount Rogers Formation - Conglomerate, graywacke, laminated siltstone, and shale.
Newark Supergroup; Jurassic Siltstone and Shale (Jurassic)
Interbedded siltstone and shale
Newark Supergroup; Triassic Sandstone, Siltstone, and Shale (Upper Triassic)
Interbedded sandstone, siltstone, and shale
Newark Supergroup; Triassic Sandstone, Siltstone, Shale, and Coal (Triassic)
Interbedded sandstone, siltstone, shale and coal
Newark Supergroup; Triassic shale and siltstone (Triassic)
Interbedded shale and siltstone
New River Formation (Pennsylvanian)
New River Formation - Sandstone, siltstone, shale, and coal.
Nolichucky and Honaker Formations (Cambrian)
Nolichucky and Honaker Formations - Dolomitic shale; dolomite and minor chert.
Nolichucky and Maryville Formations, Rogersville Shale, and Rutledge Formation (Cambrian)
Nolichucky and Maryville Formations, Rogersville Shale, and Rutledge Formation - Calcareous shale, limestone, and dolomite.
Norton Formation (Pennsylvanian)
Norton Formation - Shale, siltstone, sandstone, and coal.
Norton, New River, Lee and Pocahontas Formations Undivided (Pennsylvanian)
Norton, New River, Lee and Pocahontas Formations Undivided - Norton Formation: siltstone, shale, sandstone, and coal. New River Formation: Sandstone siltstone, shale, coal. Pocahontas Formation: Sandstone, siltstone, shale, and coal. Lee Formation: Quart
Pennington Group (Mississippian)
Pennington Group - Shale, sandstone, dusky-red mudstone, conglomerate, siltstone, and limestone.
Pocahontas Formation (Pennsylvanian)
Pocahontas Formation - Sandstone, siltstone, shale, and coal.
Pocono Formation (Mississippian)
Pocono Formation - Sandstone, conglomeratic sandstone, and shale with carbonaceous partings and impure coal beds.
Price Formation (Mississippian)
Price Formation - Sandstone, conglomeratic sandstone, and shale with carbonaceous partings and impure coal beds.
Ridgeley Sandstone, Helderberg and Cayugan Groups (Silurian-Devonian)
Ridgeley Sandstone, Helderberg and Cayugan Groups - Calcareous sandstone; partly cherty limestone; calcareous shale; fossiliferous.
Rome Formation (Cambrian)
Rome Formation - Dusky-red and green shale and siltstone, dolomite, and limestone.
Sequatchie Formation, Reedsville Shale, Trenton Limestone, Eggleston Formation (Ordovician)
Sequatchie Formation, Reedsville Shale, Trenton Limestone, Eggleston Formation - Shale, siltstone, limestone, and sandstone.
Shady Dolomite (Cambrian)
Shady Dolomite - Dolomite.
Silurian and Upper Ordovician Formations Undivided (Ordovician-Silurian)
Silurian and Upper Ordovician Formations Undivided - Includes: Skrt, Sm, Oun, Ous, Ou, Om. (Shrc and Okpl?)
Silurian Formations Undivided (Silurian)
Silurian Formations Undivided - Some landslides with intact stratigraphic units in Giles County area. Includes: Dsu, Skrt, Sm. (Shrc?)
Upper and Middle Ordovician Formations Undivided (Ordovician)
Upper and Middle Ordovician Formations Undivided - Includes: Oun, Ous, Ou, Om, Okpl, Oeln, Oml, Ols.
Waynesboro Formation (Cambrian)
Waynesboro Formation - Dolomite, dusky-red and green shale, limestone, and sandstone.
Waynesboro Formation and Tomstown Dolomite (Cambrian)
Waynesboro Formation and Tomstown Dolomite - Waynesboro Formation: Dolomite, dusky-red and green shale, limestone, and sandstone. Tomstown Dolomite: Dolomite, in part cherty.
Wise Formation (Pennsylvanian)
Wise Formation - Sandstone, shale, siltstone, and coal; quartzarenite.
Wise Formation and Gladeville Sandstone (Pennsylvanian)
Wise Formation and Gladeville Sandstone - Sandstone, shale, siltstone, and coal; quartzarenite.

Vermont

Glens Falls and Orwell Limestones, Undifferentiated (Ordovician)
Glens Falls and Orwell Limestones, Undifferentiated - Combined where deformation has made the thin bedded Glens Falls undistinguishable from the thick bedded Orwell; from West Rutland south may contain rocks as low as the Middlebury.
Glens Falls Formation, Larrabee Member (Ordovician)
Glens Falls Formation, Larrabee Member - Thin-bedded shaly limestone. (Glens Falls Formation: Thin bedded, dark blue-gray, rather coarsely granular and highly fossiliferous limestone.)
Glens Falls Formation, Shoreham Member (Ordovician)
Glens Falls Formation, Shoreham Member - Interbedded limestone and shale, contains Cryptolithus tesselatus and Prasopora orientalis. (Glens Falls Formation: Thin bedded, dark blue-gray, rather coarsely granular and highly fossiliferous limestone.)
Hortonville, or Cumberland Head, and Glens Falls Formations, Undifferentiated (Ordovician)
Hortonville, or Cumberland Head, and Glens Falls Formations, Undifferentiated - Hortonville or Cumberland Head is combined with Glens Falls where the boundary with the Glens Falls is widely covered by surficial deposits, also where the Cumberland Head thins.
Middlebury and Chazy Limestone; Undifferentiated Youngman and Carman Formations (Ordovician)
Middlebury and Chazy Limestone, Undifferentiated Youngman and Carman Formations - Dark blue-gray, somewhat nodular and granular limestone with buff dolomite and shaly interbeds a fraction of an inch thick and 2 to 4 inches apart. The Middlebury, which is east of Champlain and Orwell thrusts, and the Youngman, which is east of Highgate Springs thrust, are, due partly to deformation, more slaty in appearance than the Chazy, which is west of the major thrusts. The Carman is a quartz sandstone with shaly partings that underlies the Youngman. The Chazy contains 3 members.
Parker Slate (Cambrian)
Parker Slate - Gray to black micaceous shale and slate, includes dolomite, sandstone, and quartzite lenses; chiefly on west limb of St. Albans synclinorium.
Sweetsburg Formation, Skeels Corners Slate and Mill River Conglomerate Members Undifferentiated (Cambrian)
Sweetsburg Formation, Skeels Corners Slate and Mill River Conglomerate Members Undifferentiated - Black slate; local dolomite, sandstone, dolomite conglomerate, limestone bioherm, limestone, and calcareous shale. The Mill River is a basal limestone conglomerate.

Washington

Cambrian limestone and dolomite (Early Cambrian-Middle Ordovician)
Mostly massive dolomite, with a basal unit of gray to dark-gray limestone interbedded with limy shale, and an upper unit of fine-grained massive limestone with some marble; Pend Oreille and northern and central Stevens Counties. Three-fold division less evident in Colville area. Dolomite, with minor basal unit of interbedded limestone and phyllite in the Addy-Dunn Mountain area of Stevens County. Marble, dolomite, limestone, and limy slate in Hunters' district. Dolomitic marble in southern Stevens and northern Lincoln Counties. Middle Cambrian fossils near base in Metaline district, and Bathyuriscus-Elrathina fauna in lower unit in Leadpoint district. Phosphatic brachiopods in upper unit in Leadpoint district tentatively assigned to Middle and Upper Cambrian.
Carboniferous and Permian volcanic rocks (Devonian to Permian; Triassic in Asotin County)
Predominantly altered andesite, basalt, and diabase with interbedded chert and argillite; includes some tuff, greenstone, and spilitic volcanic rocks; northern Cascade Mountains. Mostly schistose greenstone, some agglomerate, and rarely lapilli; includes minor beds of limestone with associated argillite and graywacke; northwestern Stevens County.
Carboniferous-Permian sedimentary and volcanic rocks (Devonian to Permian; some Jurassic)
Sedimentary and volcanic rocks, undivided. Cherty and slaty argillite, siltstone, graywacke, chert, greenstone, tuff, andesite, and spilitic volcanics.
Carboniferous-Permian sedimentary and volcanic rocks (Devonian to Permian, minor Mesozoic)
Predominantly sedimentary rocks. Graywacke, argillite, and slate; includes minor marble, siltstone, arkose, conglomerate, ribbon cherts, and volcanic rocks. Some Devonian rocks may be included in northwestern Washington.
Carboniferous rocks (Late Devonian to Mississippian)
Thin-bedded graywacke, shale, argillite, slate, schist, volcanic breccia, gritstone, conglomerate, and limestone on northeast shore of Orcas Island. Limestone or dolomitic limestone, apparently interbedded with limy argillite and graywacke, forms belt of small separate outcrops between Springdale and Valley in southeastern Stevens County. Late Devonian to Early Pennsylvanian in age.
Cretaceous nonmarine rocks (Late Cretaceous)
Redbeds of thick-bedded sandstone, shale, and pebble conglomerate in upper Methow River area of Okanogan County.
Cretaceous sedimentary rocks, mostly marine (Late Cretaceous; possibly Eocene)
Cretaceous conglomerate, sandstone, shale, breccia, limestone, and gritstone in San Juan Islands.
Cretaceous sedimentary rocks, mostly marine (Cretaceous)
Upper Cretaceous black siltstone, graywacke, and silica pebble conglomerate in western Okanogan County.
Eocene nonmarine rocks (Eocene)
Predominantly sandstone and shale. Includes some conglomerate in the Cle Elum area in Kittilas County. Contains extensive coal seams near Roslyn and carbonaceous shale and coal beds in White Pass area. Contains tuff beds in northwestern Ferry County.
Eocene-Oligocene volcanic rocks (Eocene-Oligocene)
Predominantly light-green, bedded andesite breccia with interbedded andesite and basalt flows, mudflows, and tuff beds; becomes more tuffaceous near top of unit. Includes tuffaceous and arkosic sandstone, shale, and carbonaceous shale beds in central and southern Cascade Mountians. Rhyodacite and quartz latite flows in northwestern Ferry County.
Lower Tertiary volcanic rocks, undivided (Eocene)
Predominantly andesite flows and flow breccia; includes basalt flows, minor rhyolitic rocks, and some sedimentary rocks.
Lower upper Eocene marine and nonmarine rocks (Eocene)
Predominantly massive to well-bedded tuffaceous marine siltstone with interbedded arkosic and basaltic sandstone. Includes conglomerate in King County and along north side of Olympic Peninsula. Minor lava flows and breccia in western Lewis County and eastern Grays Harbor County. Coal seams in central Lewis County and north-central Pierce County.
Mesozoic volcanic rocks, undivided (Jurassic)
Includes latite, andesite and basalt flows, tuff, and agglomerate. Interbedded sedimentary rocks in Orient area of Stevens County.
Miocene marine rocks (Miocene)
Massive to thin-bedded, friable, basaltic to feldspathic sandstone, with shale, siltstone, and local pebble conglomerate interbeds.
Miocene nonmarine rocks (Late Miocene)
Poorly to moderately consolidated tuffaceous sandstone, conglomerate, siltstone, and claystone in western Washington. Chiefly clay and shale with minor sand, gravel, and diatomaceous earth near Spokane. Includes diatomite beds near Yakima and Quincy, and some marine beds in Western Washington.
Oligocene-Miocene marine rocks (Oligocene)
Massive to thin-bedded, coarse-grained sandstone, conglomerate, conglomeratic sandstone, shale, and sandy shale.
Oligocene volcanic rocks (Oligocene)
Andesite and rhyodacite flows, tuff, and tuffaceous sandstones of northern Lincoln County and southwestern Stevens County.
Paleocene-Cretaceous nonmarine rocks (Eocene (see age coding))
Brown-gray to light-gray, medium- to course-grained massive cross-bedded arkose with interbedded conglomerate and siltstone. Contains several coal seams in Whatcom County. Iron-rich laterite at base near Cle Elum and Blewett Pass in Kittitas and Chelan Counties.
Pliocene nonmarine rocks (Pliocene)
Conglomerate, sandstone, shale, and mudstone. Tuffaceous in part; contains alluvial fan type material locally.
Tertiary nonmarine rocks, undivided (Tertiary; mostly Eocene)
Sandstone, shale, conglomerate, agglomerate, and tuff; includes some lava flows. Massive conglomerate, sandstone, siltstone, and ferruginous shale in northwestern Whatcom County.
Upper Eocene volcanic rocks (Late-Middle Eocene)
Rhyolite flows and some interbedded tuff beds in Cle Elum area, Kittitas County.
Upper Eocene volcanic rocks (Late Eocene to Oligocene)
Predominantly basalt flows and flow breccia; includes some pyroclastic and andesite rocks. Chiefly in western Washington.
Upper Jurassic-Lower Cretaceous sedimentary and volcanic rocks (Late Cretaceous-Jurassic)
Sedimentary and volcanic rocks, undivided. Graywacke, argillite, siltstone, slate, volcanic rocks, phyllite, greenschist, and greenstone.
Upper upper Eocene nonmarine and marine rocks (Middle Eocene)
Massive to thin-bedded, feldspathic to arkosic sandstone, siltstone, shale, and carbonaceous shale; becomes mostly marine in the western foothills of Cascade Mountains where coal beds are abundant. Basaltic sandstone and siltstone in northern Olympic Peninsula.

Wisconsin

West Virginia

Allegheny Formation (Pennsylvanian)
Allegheny Formation - cyclic sequences of sandstone, siltstone, shale, limestone, and coal. Includes the Freeport, Kittanning and Clarion coals, also, the Princess coals of Kentucky . Extends from the top of the Upper Freeport coal to the top of the Homewood Sandstone.
Bluefield Formation (Mississippian)
Bluefield Formation (part of Mauch Chunk Group) - red and green shale and sandstone, with a few thin limestone lenses, such as the Reynolds.
Bluestone and Princeton Formations (Mississippian)
Bluestone and Princeton Formations (part of Mauch Chunk Group) - the Bluestone Formation is mostly red, green, and medium-gray shale and sandstone; Princeton Sandstone is underneath.
Brallier Formation (Devonian)
Brallier Formation - predominantly olive-gray to dark, thickly laminated marine shale, with considerable siltstone and thin sandstone lenses; mainly nonfossiliferous.
Brallier Formation and Harrell Shale, undivided (Devonian)
Brallier Formation and Harrell Shale, undivided - Brallier Formation : predominantly olive-gray to dark, thickly laminated marine shale, with considerable siltstone and thin sandstone lenses; mainly nonfossiliferous. Harrell Shale: dark gray to black thinly laminated to fissile shale. Calcareous shale and limestone lenses near the base (Tully).
Chemung Group (Devonian)
Chemung Group - gray to brown siltstone and sandstone with shale and conglomeratic interbeds; mainly marine and sparingly fossiliferous; boundaries gradational. Can be divided into the Voreknobs and Scherr Formations along the Allegheny Front. Parkhead Sandstone Member near base.
Conemaugh Group (Pennsylvanian)
Conemaugh Group - cyclic sequences of red and gray shale, siltstone, and sandstone, with thin limestones and coals. Mostly non-marine. May be divided into Casselman and Glenshaw Formations. Extends from the base of the Pittsburgh coal to the top of the Upper Freeport coal. Includes the Elk Lick, Bakerstown, and Mahoning coals, and the Ames and Brush Creek Limestones.
Dunkard Group (Permian/Pennsylvanian)
Dunkard Group - non-marine cyclic sequences of sandstone, siltstone, red and gray shale, limestone, and coal. Contains the Greene, Washington and Waynesburg Formations. Extends from the top of the exposed bed rock section to the top of the Waynesburg coal. Includes the Washington coals and limestones. Palynological evidence favors a Pennsylvanian age, at least for the lower portion.
Elbrook Formation (Cambrian)
Elbrook Formation - thin-bedded blue-gray argillaceous limestone and platy shale, with some siliceous limestone and minor dolomite.
Greenbrier Group (Mississippian)
Greenbrier Group - marine limestone and marine and non-marine red and gray shale, and minor sandstone beds in numerous formational units.
Hampshire Formation (Devonian)
Hampshire Formation - non-marine shales and fine micaceous sandstones, mostly red to brownish-gray, including siltstone, sandstone and conglomerate. Generally distinguishable from the underlying Chemung by non-marine character and red color.
Harrell Shale (Devonian)
Harrell Shale (part of Millboro Shale) - dark gray to black thinly laminated to fissile shale. Calcareous shale and limestone lenses near the base (Tully).
Helderberg Group (Devonian)
Helderberg Group - mostly cherty limestone, with some sandstone and shale. Contains several named stratigraphic units, including the Keyser Formation, which is partly Silurian and includes the Clifton Forge Sandstone and Big Mountain Shale Members.
Hinton Formation (Mississippian)
Hinton Formation (part of Mauch Chunk Group) - red, green, and medium-gray shale and sandstone, with a few thin limestone beds, including the Avis.
Juniata and Oswego Formations (Ordovician)
Juniata and Oswego Formations - the Juniata is a thin-bedded, blocky, red sandstone and shale. In places it is underlain by the thick-bedded, gray Oswego Sandstone.
Kanawha Formation (Pennsylvanian)
Kanawha Formation (part of Pottsville Group) - sandstone (approx 50%), shale, siltstone, and coal. Contains several marine zones. Becomes more shaly westward in the subsurface. Extends from the top of the Homewood Sandstone to the top of the Upper Nuttall Sandstone. Includes the Stockton (Mercer), Coalburg, Winifrede, Chilton, Williamson, Cedar Grove, Alma, Peerless, Campbell Creek, Powellton, Eagle, Gilbert, and Douglas coals.
Maccrady Formation (Mississippian)
Maccrady Formation - red shale and mudrock, red and green sandstone, and minor limestone. Present only from Pendleton County southward. Contains rock salt and gypsum in southwestern Virginia.
Maccrady Formation and Pocono Group, undivided (Mississippian)
Maccrady Formation and Pocono Group, undivided - Maccrady Formation: red shale and mudrock, red and green sandstone, and minor limestone. Present only from Pendleton County southward. Contains rock salt and gypsum in southwestern Virginia. Pocono Group: predominantly hard gray massive sandstones, with some shale. In the Eastern Panhandle, has been divided into the Hedges, Purslane, and Rockwell Formations.
Mahantango Formation (Devonian)
Mahantango Formation (part of Millboro Shale) - thickly laminated marine shale, siltstone, very fine sandstone, and some limestone, with an occasional coral reef or biostrome. Contains the Clearville and Chaneysville Siltstone Members of Pennsylvania.
Marcellus Formation and Needmore Shale, undivided (Devonian)
Marcellus Formation and Needmore Shale, undivided - Marcellus Formation (part of Millboro Shale): predominantly gray-black to black thinly laminated non-calcareous pyritic shale. Contains one or more thin-bedded limestones, including the Purcell Member of Pennsylvania. Needmore Shale (part of Onesquethaw ("Onondaga") Group): predominantly dark grey or green, calcitic, mostly non-fissile shale. Gives strong "kick" on gamma ray logs. Tioga Bentonite near the top. Includes the black Beaver Dam Shale Member. Grades westward into the Huntersville Chert. Not mappable at scale of this map. Included with Dmn.
Martinsburg Formation (Ordovician)
Martinsburg Formation - predominantly gray to dark shale, yellowish in the upper portion. Contains scattered thin limestone and sandstone interbeds, particularly in the lower portion. The upper portion constitutes the Reedsville Shale.
Mauch Chunk Group (Mississippian)
Mauch Chunk Group - red, green, and medium-gray shale and sandstone, with a few thin limestones.
McKenzie Formation and Clinton Group (Silurian)
McKenzie Formation and Clinton Group - includes the McKenzie Formation, consisting of shale with thin limestone lenses; the dark Rochester Shale; the white Keefer Sandstone; and the Rose Hill predominantly red shale, with thin sandstone interbeds, some of which are called "iron sandstones" from their reddish-brown color and hematite content.
McKenzie Formation, Clinton Group and Tuscarora Sandstone, undivided (Silurian)
McKenzie Formation, Clinton Group and Tuscarora Sandstone, undivided - McKenzie Formation and Clinton Group: includes the McKenzie Formation, consisting of shale with thin limestone lenses; the dark Rochester Shale; the white Keefer Sandstone; and the Rose Hill predominantly red shale, with thin sandstone interbeds, some of which are called "iron sandstones" from their reddish-brown color and hematite content. Tuscarora Sandstone: medium- to thick-bedded, white to gray or pinkish sandstone, fine to coarse, quartzitic, ridge-forming. Equivalent to the Clinch Sandstone of Tennessee.
Middle and Upper Devonian, undivided (Devonian)
Middle and Upper Devonian, undivided - this unit is predominantly shale, and includes all Devonian beds above the Onesquethaw. Consists of units: Hampshire Formation, Chemung Group, Brallier Formation, Harrell Shale, Mahantango Formation, and Marcellus Formation.
Millboro Shale (Devonian)
Millboro Shale - dark grey to black shale facies of eastern West Virginia. Consists of units: Harrell Shale, Mahantango Formation and Marcellus Formation.
Monongahela Group (Pennsylvanian)
Monongahela Group - non-marine cyclic sequences of sandstone, siltstone, red and gray shale, limestone, and coal. Contains the Uniontown and Pittsburgh Formations. Extends from the top of the Waynesburg coal to the base of the Pittsburgh coal. Includes the Waynesburg, Uniontown, Sewickley, Redstone and Pittsburgh coals. Thickness is 170 feet in Mineral and Grant Counties.
New River Formation (Pennsylvanian)
New River Formation (part of Pottsville Group) - predominantly sandstone, with some shale, siltstone, and coal. Grades to nearly all sandstone in the subsurface. Extends from the top of the Upper Nuttall Sandstone to the top of the Flattop Mountain Sandstone. Includes the Iaeger, Sewell, Welch, Raleigh, Beckley, Fire Creek, and Pocahontas Nos. 8 and 9 coals.
Oriskany Sandstone and Helderberg Group, undivided (Devonian)
Oriskany Sandstone and Helderberg Group, undivided - Oriskany Sandstone: sometimes designated Ridgeley in eastern West Virginia. White to brown coarse- to fine-grained, partly calcareous sandstone, locally pebbly or conglomeratic, and ridge-forming. May be white, nearly pure silica, and a source of glass sand, as at Berkeley Springs, Morgan County. Helderburg Group: mostly cherty limestone, with some sandstone and shale. Contains several named stratigraphic units, including the Keyser Formation, which is partly Silurian and includes the Clifton Forge Sandstone and Big Mountain Shale Members.
Pocahontas Formation (Pennsylvanian)
Pocahontas Formation (part of Pottsville Group) - sandstone, approx. 50%, with some shale, siltstone, and coal. Extends from the top of the Flattop Mountain Sandstone to the top of the Mississippian. Includes from bottom upward Pocahontas coals Nos. 1 through 7.
Pocono Group (Mississippian)
Pocono Group - predominantly hard gray massive sandstones, with some shale. In the Eastern Panhandle, has been divided into the Hedges, Purslane, and Rockwell Formations.
Pottsville Group (Pennsylvanian)
Pottsville Group - includes the Kanawha, New River, and Pocahontas Formations. Predominantly sandstones, some of which are conglomeratic, with thin shales and coals. Undivided in northern West Virginia.
Tonoloway, Wills Creek, and Williamsport Formations (Silurian)
Tonoloway, Wills Creek, and Williamsport Formations - includes the thin-bedded platy argillaceous limestones of the Tonoloway, the thin-bedded shale with fossiliferous limestones of the Wills Creek, the Bloomsburg red clastic facies, and the greenish-brown to white Williamsport Sandstone. The Wills Creek contains anhydrite and rock salt, the latter supplying brine from deep wells along the Ohio River.
Waynesboro Formation (Cambrian)
Waynesboro Formation - variegated shale and sandstone, commonly red or brown. Middle zone contains much dolomite and limestone. Contains the Olenellus fauna of Early Cambrian age, although its upper portion may be of Middle Cambrian age.
Weverton-Loudoun Formation (Cambrian)
Weverton-Loudoun Formation (Chilhowee Group) - tough quartzitic sandstones, conglomerates, and shale.

Wyoming

Baxter Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
BAXTER SHALE--Gray to black soft sandy shale and shaly sandstone.
Bear River Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
BEAR RIVER FORMATION--Black shale, fine-grained brown sandstone, thin limestone, and bentonite beds.
Bighorn Dolomite, Gallatin Limestone, and Gros Ventre Formation (TB), Bighorn Dolomite, Snowy Range Formation, Pilgrim Limestone, Park Shale, Meagher Limestone, Wolsey Shale, and Flathead Sandstone (Y), Bighorn Dolomite, Gallatin Limestone, Gros Ventre Formation, and Flathead Sandstone (N), or Whitewood Dolomite, and WInnipeg and Deadwood Formations (NE) (Phanerozoic | Paleozoic | Cambrian-Middle Cambrian-Furongian(?) Ordovician-Early(?) Ordovician-Middle(?) Ordovician-Late)
BIGHORN DOLOMITE, GALLATIN LIMESTONE, and GROS VENTRE FORMATION. BIGHORN DOLOMITE (Thrust Belt)--Gray massive cliff-forming siliceous dolomite and locally dolomitic limestone. GALLATIN LIMESTONE--Gray and tan limestone. GROS VENTRE FORMATION--Greenish-gray micaceous shale. BIGHORN DOLOMITE, SNOWY RANGE FORMATION, PILGRIM LIMESTONE, PARK SHALE, MEAGHER LIMESTONE, WOLSEY SHALE, AND FLATHEAD SANDSTONE (Yellowstone). BIGHORN DOLOMITE--Light-gray massive siliceous dolomite. SNOWY RANGE FORMATION (Gallatin Group)--Medium-gray limestone and underlying greenish-gray shale. PILGRIM LIMESTONE (Gallatin Group)--Blue-gray and yellow mottled hard limestone. PARK SHALE--Green micaceous soft shale. Upper part may be Late Cambrian. MEAGHER LIMESTONE--Blue-gray and yellow mottled hard limestone. WOLSEY SHALE--Green micaceous soft shale. FLATHEAD SANDSTONE--Dull-red quartzitic sandstone. BIGHORN DOLOMITE, GALLATIN LIMESTONE, GROS VENTRE FORMATION, AND FLATHEAD SANDSTONE (north Wyoming). BIGHORN DOLOMITE--Gray massive cliff-forming siliceous dolomite and locally dolomitic limestone. GALLATIN LIMESTONE--Blue-gray and yellow mottled hard dense limestone. GROS VENTRE FORMATION--Soft green micaceous shale (Upper and Middle Cambrian Park Shale Member), underlain by blue-gray and yellow mottled hard dense limestone (Middle Cambrian Death Canyon Limestone Member), and soft green micaceous shale (Middle Cambrian Wolsey Shale Member). FLATHEAD SANDSTONE--Dull-red quartzitic sandstone. WHITEWOOD DOLOMITE, AND WINNIPEG AND DEADWOOD FORMATIONS (northeast Wyoming). WHITEWOOD DOLOMITE--Buff massive fossiliferous dolomite. WINNIPEG FORMATION--Pink to yellow siltstone and shale. DEADWOOD FORMATION--Red and brown quartzitic sandstone.
Carlile Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
CARLILE SHALE--Dark-gray sandy shale; Sage Breaks Member at top; Turner Sandy Member in middle.
Chugwater and Goose Egg Formations (Phanerozoic | Paleozoic Mesozoic | Permian Triassic-Early(?) Triassic-Middle(?) Triassic-Late)
CHUGWATER AND GOOSE EGG FORMATIONS (north Wyoming). CHUGWATER FORMATION--Red siltstone and shale. Alcova Limestone Member in upper middle part in north Wyoming. Thin gypsum partings near base in north and northeast Wyoming. GOOSE EGG FORMATION--Red sandstone and siltstone, white gypsum, halite, and purple to white dolomite and limestone; CHUGWATER FORMATION OR GROUP (south Wyoming)--Red shale and siltstone containing thin gypsum partings near base. Group includes Popo Agie Formation (red shale and red, yellow, and purple siltstone; lenses of lime-pellet conglomerate), Crow Mountain Sandstone (red and gray, thick bedded), Alcova Limestone, and Red Peak Formation (red siltstone and shale). Chugwater Formation includes as members all the units listed above. Includes overlying Jelm Formation in Shirley and Seminoe Mountains and at northern end of Laramie Basin. JELM FORMATION--Red sandstone. GOOSE EGG FORMATION--Red sandstone and siltstone, white gypsum, halite, and purple to white dolomite and limestone.
Chugwater Formation (N, NE), or Chugwater Formation or Group (S) (Phanerozoic | Mesozoic | Triassic-Early Triassic-Middle(?) Triassic-Late)
CHUGWATER FORMATION (north, northeast Wyoming)--Red siltstone and shale. Alcova Limestone Member in upper middle part in north Wyoming. Thin gypsum partings near base in north and northeast Wyoming. [None mapped in the NE]; CHUGWATER FORMATION OR GROUP (south Wyomingt)--Red shale and siltstone containing thin gypsum partings near base. Group includes Popo Agie Formation (red shale and red, yellow, and purple siltstone; lenses of lime-pellet conglomerate), Crow Mountain Sandstone (red and gray, thick bedded), Alcova Limestone, and Red Peak Formation (red siltstone and shale). Chugwater Formation includes as members all the units listed above. Includes overlying Jelm Formation in Shirley and Seminoe Mountains and at northern end of Laramie Basin. JELM FORMATION--Red sandstone.
Cody Shale (Phanerozoic | Mesozoic | Cretaceous-Late (78-83 Ma))
CODY SHALE (AGE 78 TO 83 Ma) northern Yellowstone area--Gray to brown shale and siltstone; north and south Wyoming--Dull-gray shale, gray siltstone, and fine-grained gray sandstone.
Ferris Formation (Phanerozoic | Mesozoic Cenozoic | Cretaceous-Late Tertiary | Paleocene)
FERRIS FORMATION--Brown and gray sandstone and shale; sparse carbonaceous shale and coal beds; thin lenses of pebble conglomerate.
Forelle Limestone and Satanka Shale (Phanerozoic | Paleozoic | Permian)
FORELLE LIMESTONE AND SATANKA SHALE. FORELLE LIMESTONE--Thin-bedded limestone. Locally is a member of the Goose Egg Formation. SATANKA SHALE--Red shale .
Fort Union Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene )
FORT UNION FORMATION northwest, southwest, and central Wyoming--Brown to gray sandstone, gray to black shale, and thin coal beds; east Wyoming--Light-colored massive sandstone, drab shale, and thick coal beds.
Fort Union Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene )
FORT UNION FORMATION Tongue River Member--Thick beds of yellow sandstone interbedded with gray and black shale and many coal beds.
Fort Union Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene )
FORT UNION FORMATION Tullock Member--Soft gray sandstone, gray and brown carbonaceous shale, and thin coal beds.
Fort Union Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene )
FORT UNION FORMATION Lebo Member--Dark-gray clay shale and concretionary sandstone.
Fox Hills Sandstone (Phanerozoic | Mesozoic | Cretaceous-Late)
FOX HILLS SANDSTONE--Light-colored sandstone and gray sandy shale containing marine fossils.
Fox Hills Sandstone and Bearpaw Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
FOX HILLS SANDSTONE AND BEARPAW SHALE. FOX HILLS SANDSTONE (Kfh)--Light-colored sandstone and gray sandy shale containing marine fossils. BEARPAW SHALE--Dark-greenish-gray shale containing thin gray sandstone partings.
Fox Hills Sandstone and Lewis Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
FOX HILLS SANDSTONE AND LEWIS SHALE. FOX HILLS SANDSTONE (Kfh)--Light-colored sandstone and gray sandy shale containing marine fossils. LEWIS SHALE (AGE ABOUT 68 Ma) (Kle)--Gray marine shale containing many gray and brown lenticular concretion-rich sandstone beds.
Frontier Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
FRONTIER FORMATION in thrust belt--White to brown sandstone and dark-gray shale; oyster coquina in upper part; coal and lignite in lower part; in north and south Wyoming--Gray sandstone and sandy shale.
Frontier Formation and Mowry and Thermopolis Shales (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Middle(?) Cretaceous-Late)
FRONTIER FORMATION (Kf) AND MOWRY (Kmr) AND THERMOPOLIS SHALES. FRONTIER FORMATION--Gray sandstone and sandy shale. In Northern Yellowstone area, Yellowish- to medium-gray sandstone; tuffaceous and carbonaceous in lower part. MOWRY SHALE (AGE 94 TO 98 Ma)--Silvery-gray hard siliceous shale containing abundant fish scales and bentonite beds. THERMOPOLIS SHALE--Black soft fissile shale; Muddy Sandstone Member at top.
Gallatin Limestone, Gros Ventre Formation and equivalents, and Flathead Sandstone (N) or Cambrian Rocks (S) (Phanerozoic | Paleozoic | Cambrian-Middle Cambrian-Furongian)
GALLATIN LIMESTONE, GROS VENTRE FORMATION and equivalents, and FLATHEAD SANDSTONE (north Wyoming). GALLATIN LIMESTONE--Blue-gray and yellow mottled hard dense limestone. GROS VENTRE FORMATION--Soft green micaceous shale (Upper and Middle Cambrian Park Shale Member), underlain by blue-gray and yellow mottled hard dense limestone (Middle Cambrian Death Canyon Limestone Member), and soft green micaceous shale (Middle Cambrian Wolsey Shale Member). FLATHEAD SANDSTONE--Dull-red quartzitic sandstone. CAMBRIAN ROCKS (south Wyoming). South flank of Granite Mountains--Blue-gray and yellow mottled hard dense limestone interbedded with soft green micaceous shale; dull-red quartzitic sandstone at base. On and south of Rawlins uplift--Glauconitic quartzitic sandstone.
Green River and Wasatch Formations (Phanerozoic | Cenozoic | Tertiary | Eocene)
GREEN RIVER AND WASATCH FORMATIONS -- in Thrust Belt: GREEN RIVER FORMATION--Buff laminated marlstone and limestone, brown oil shale, and siltstone. Includes Angelo and Fossil Butte Members. WASATCH FORMATION--Variegated mudstone and sandstone. Includes Tunp and Bullpen Members, other tongues and unnamed members, and main body (variegated red to gray, brown, and gray mudstone and sandstone; conglomerate lenses); in southwest Wyoming -- GREEN RIVER FORMATION--Oil shale, light-colored tuffaceous marlstone, and sandstone. WASATCH FORMATION--Drab to variegated claystone and siltstone, carbonaceous shale and coal, buff sandstone, arkose, and conglomerate. In northwestern part of Green River Basin is thick arkosic light-yellowish-tan sandstone intertonguing with pale-green to gray claystone and shale.
Green River Formation: Fontenelle Tongue or Member [NONE ON MAP] (Phanerozoic | Cenozoic | Tertiary | Eocene)
WASATCH AND GREEN RIVER FORMATIONS: New Fork Tongue (dull-red and green mudstone, brown sandstone, and thin limestone beds, merging southward in T. 23 N. with other units) of Wasatch and Fontenelle Tongue or Member (oil shale, marlstone, limestone, and siltstone; occurs along Green and New Fork Rivers and on west side of Green River Basin from T. 33 N. south to and lensing out in T. 17 N.) of Green River.
Green River Formation: Wilkins Peak Member and Tipton Shale member or Tongue (Phanerozoic | Cenozoic | Tertiary | Eocene)
GREEN RIVER FORMATION Wilkins Peak Member (age about 49 Ma) (green, brown, and gray tuffaceous sandstone, shale, and marlstone; contains evaporites in subsurface sections) and Tipton Shale Member or Tongue (oil shale and marlstone).
Hartville Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early Pennsylvanian-Middle(?) Pennsylvanian-Late(?) Permian)
HARTVILLE FORMATION--Red and white sandstone underlain by gray dolomite and limestone, red shale, and red and gray sandstone. Lowermost unit may be Late Mississippian in age.
Lance Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
LANCE FORMATION north Wyoming--Thick-bedded buff sandstone and drab to green shale; thin conglomerate lenses; south and northeast Wyoming--Brown and gray sandstone and shale; thin coal and carbonaceous shale beds.
Lewis Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
LEWIS SHALE (AGE ABOUT 68 Ma)--Gray marine shale containing many gray and brown lenticular concretion-rich sandstone beds.
Madison Limestone, Darby Formation, Bighorn Dolomite, Gallatin Limestone, Gros Ventre Formation, and Flathead Sandstone (N), Madison Limestone and Cambrian rocks (S), Minnekahta Limestone, Opeche Shale, Minnelusa Formation, Pahasapa and Englewood Limestones, Whitewood Dolomite, Winnipeg and Deadwood Formations (NE), or Paleozoic, undifferentiated (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian(?) Devonian(?) Carboniferous(?) Permian)
MADISON LIMESTONE, DARBY FORMATION, BIGHORN DOLOMITE, GALLATIN LIMESTONE, GROS VENTRE FORMATION, AND FLATHEAD SANDSTONE (north Wyoming). MADISON LIMESTONE OR GROUP--Group includes Mission Canyon Limestone (blue-gray massive limestone and dolomite), underlain by Lodgepole Limestone (gray cherty limestone and dolomite). DARBY FORMATION--Yellow and greenish-gray shale and dolomitic siltstone underlain by fetid brown dolomite and limestone. BIGHORN DOLOMITE--Gray massive cliff-forming siliceous dolomite and locally dolomitic limestone. GALLATIN LIMESTONE--Blue-gray and yellow mottled hard dense limestone. GROS VENTRE FORMATION--Soft green micaceous shale (Upper and Middle Cambrian Park Shale Member), underlain by blue-gray and yellow mottled hard dense limestone (Middle Cambrian Death Canyon Limestone Member), and soft green micaceous shale (Middle Cambrian Wolsey Shale Member). FLATHEAD SANDSTONE--Dull-red quartzitic sandstone. MADISON LIMESTONE AND CAMBRIAN ROCKS (south Wyoming). MADISON LIMESTONE--Includes Mission Canyon Limestone (blue-gray massive limestone and dolomite), underlain by Lodgepole Limestone (gray cherty limestone and dolomite). CAMBRIAN ROCKS--On south flank of Granite Mountains, blue-gray and yellow mottled hard dense limestone interbedded with soft green micaceous shale; dull-red quartzitic sandstone at bae. On and south of Rawlins uplift, glauconitic quartzitic sandstone. MINNEKAHTA LIMESTONE, OPECHE SHALE, MINNELUSA FORMATION, PAHASAPA AND ENGLEWOOD LIMESTONES, WHITEWOOD DOLOMITE, AND WINNIPEG AND DEADWOOD FORMATIONS--Various combinations (northeast Wyoming). MINNEKAHTA LIMESTONE--Gray slabby hard limestone. Locally is a member of the Goose Egg Formation. OPECHE SHALE--Red soft sandy shale. Locally is a member of the Goose Egg Formation. MINNELUSA FORMATION--Buff and red limy sandstone; some thin limestone beds, solution breccias, and gypsum. PAHASAPA LIMESTONE--Gray massive dolomititc limestone. ENGLEWOOD LIMESTONE--Pink slabby dolomitic limestone. WHITEWOOD DOLOMITE--Buff massive fossiliferous dolomite. WINNIPEG FORMATION--Pink to yellow siltstone and shale. DEADWOOD FORMATION--Red and brown quartzitic sandstone. PALEOZOIC ROCKS, undifferentiated (Thrust Belt).
Medicine Bow Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
MEDICINE BOW FORMATION--Brown and gray sandstone and shale; thin coal and carbonaceous shale beds.
Mesaverde Formation (N) or Mesaverde Group (S) (Phanerozoic | Mesozoic | Cretaceous-Late)
MESAVERDE FORMATION (north Wyoming)--Light-colored massive to thin-bedded sandstone, gray sandy shale, and coal beds. In Jackson Hole locally contains gold-bearing quartzite conglomerate. North of North Fork Powder River east of the Bighorn Mountains, consists solely of the Parkman Sandstone Member; MESAVERDE GROUP (SOUTH WYOMING). Includes Almond Formation, Ericson Sandstone, Rock Springs and Blair Formations in Rock Springs uplift; Almond Formation (white and brown soft sandstone, gray sandy shale, coal and carbonaceous shale), Pine Ridge Sandstone (light-gray sandstone and thin coal beds), and Allen Ridge (gray sandstone, shale, and thin coal beds) and Haystack Mountains (gray marine sandstone and shale) Formations in Rawlins uplift; Pine Ridge Sandstone (light-gray sandstone and thin coal beds) and Rock River Formation (soft sandstone and sandy shale) in Laramie Basin.
Mesaverde Group, Almond Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
MESAVERDE GROUP (SOUTH WYOMING). Rock Springs uplift. Almond Formation--White and brown soft sandstone, gray sandy shale, coal, and carbonaceous shale.
Mesaverde Group, Blair Formation. (Phanerozoic | Mesozoic | Cretaceous-Late)
MESAVERDE GROUP (SOUTH WYOMING). Rock Springs uplift. Blair Formation--Drab-yellow and brown sandstone and sandy shale.
Minnekahta Limestone and Opeche Shale (Phanerozoic | Paleozoic | Permian)
MINNEKAHTA LIMESTONE AND OPECHE SHALE. MINNEKAHTA LIMESTONE--Gray slabby hard limestone. Locally is a member of the Goose Egg Formation. OPECHE SHALE--Red soft sandy shale. Locally is a member of the Goose Egg Formation.
Mowry and Thermopolis Shales (Phanerozoic | Mesozoic | Cretaceous-Early)
MOWRY (Kmr) AND THERMOPOLIS SHALES. MOWRY SHALE (AGE 94 TO 98 Ma)--Silvery-gray hard siliceous shale containing abundant fish scales and bentonite beds. THERMOPOLIS SHALE--Black soft fissile shale; Muddy Sandstone Member at top.
Mowry Shale (Phanerozoic | Mesozoic | Cretaceous-Early)
MOWRY SHALE (AGE 94 TO 98 Ma)--Silvery-gray hard siliceous shale containing abundant fish scales and bentonite beds.
Newcastle Sandstone and Skull Creek Shale (Phanerozoic | Mesozoic | Cretaceous-Early)
NEWCASTLE SANDSTONE AND SKULL CREEK SHALE. NEWCASTLE SANDSTONE--Gray sandstone and sandy shale containing some bentonite and coal. SKULL CREEK SHALE--Black soft fissile shale.
Niobrara and Frontier Formations, and Mowry and Thermopolis Shales (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Middle(?) Cretaceous-Late)
NIOBRARA (Kn) AND FRONTIER (Kf) FORMATIONS, AND MOWRY (Kmr) AND THERMOPOLIS SHALES. NIOBRARA FORMATION (AGE ABOUT 83 Ma)--Light-colored limestone and gray to yellow speckled limy shale. FRONTIER FORMATION--Gray sandstone and sandy shale. MOWRY SHALE (AGE 94 TO 98 Ma)--Silvery-gray hard siliceous shale containing abundant fish scales and bentonite beds. THERMOPOLIS SHALE--Black soft fissile shale; Muddy Sandstone Member at top.
Niobrara Formation and Carlile Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
NIOBRARA FORMATION (Kn) AND CARLILE SHALE (Kcl). NIOBRARA FORMATION (AGE ABOUT 83 Ma)--Light-colored limestone and gray to yellow speckled limy shale. CARLILE SHALE--Dark-gray sandy shale; Sage Breaks Member at top; Turner Sandy Member in middle.
Nugget Sandstone, Ankareh Formation, Thaynes Limestone, Woodside Shale, and Dinwoody Formation (TB), or Nugget Sandstone and Chugwater and Dinwoody Formations (N) (Phanerozoic | Mesozoic | Triassic-Early Triassic-Middle(?) Triassic-Late(?) Triassic(?) Jurassic(?))
NUGGET SANDSTONE, ANKAREH FORMATION, THAYNES LIMESTONE, WOODSIDE SHALE, and DINWOODY FORMATION (Thrust Belt). NUGGET SANDSTONE--Buff to pink crossbedded well-sized and well-sorted quartz sandstone and quartzite; locally has oil and copper-silver-zinc mineralization. ANKAREH FORMATION--Red and maroon shale and purple limestone. THAYNES LIMESTONE--Gray limestone and limy siltstone. WOODSIDE SHALE--Red siltstone and shale. DINWOODY FORMATION--Gray to olive-drab dolomitic siltstone. NUGGET SANDSTONE AND CHUGWATER AND DINWOODY FORMATIONS (north Wyoming). NUGGET SANDSTONE--Gray to dull-red, crossbedded quartz sandstone. CHUGWATER FORMATION--Red siltstone and shale. Alcova Limestone Member in upper middle part in north Wyoming. Thin gypsum partings near base in north and northeast Wyoming. DINWOODY FORMATION--Olive-drab hard dolomitic thin-bedded siltstone.
Phosphoria Formation (Phanerozoic | Paleozoic | Permian)
PHOSPHORIA FORMATION AND RELATED ROCKS--Thrust Belt: Upper part is dark- to light-gray chert and shale with black shale and phosphorite at top; lower part is black shale, phosphorite, and cherty dolomite; north Wyoming: Brown sandstone and dolomite, cherty phosphatic and glauconitic dolomite, phosphatic sandstone and dolomite, and greenish-gray to black shale. Intertonguing equivalents of parts of Phosphoria are Park City Formation (primarily cherty dolomite, limestone, and phosphatic gray shale) and Shedhorn Sandstone.
Phosphoria, Wells, and Amsden Formations (TB), Phosphoria Formation and related rocks, Quadrant Sandstone, and Amsden Formation (Y), or Phosphoria Formation and related rocks, Tensleep Sandstone, and Amsden Formation (N) (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late Pennsylvanian(?) Permian)
PHOSPHORIA, WELLS, AND AMSDEN FORMATIONS (Thrust Belt). PHOSPHORIA FORMATION--Upper part is dark- to light-gray chert and shale with black shale and phosphorite at top; lower part is black shale, phosphorite, and cherty dolomite. WELLS FORMATION--Gray limestone interbedded with yellow limy sandstone. AMSDEN FORMATION--Red and gray cherty limestone and shale, sandstone, and conglomerate. PHOSPHORIA FORMATION AND RELATED ROCKS, QUADRANT SANDSTONE, AND AMSDEN FORMATION (Yellowstone). PHOSPHORIA FORMATION AND RELATED ROCKS--Brown sandstone and dolomite, cherty phosphatic and glauconitic dolomite, phosphatic sandstone and dolomite, and greenish-gray to black shale. Intertonguing equivalent is Shedhorn Sandstone. QUADRANT SANDSTONE--Light-gray sandstone. AMSDEN FORMATION--Red and green dolomitic shale, siltstone, and sandstone. PHOSPHORIA FORMATION AND RELATED ROCKS, TENSLEEP SANDSTONE, AND AMSDEN FORMATION (north Wyoming). PHOSPHORIA FORMATION AND RELATED ROCKS--Brown sandstone and dolomite, cherty phosphatic and glauconitic dolomite, phosphatic sandstone and dolomite, and greenish-gray to black shale. Intertonguing equivalents of parts of Phosphoria are Park City Formation (primarlily cherty dolomite, limestone, and phosphatic gray shale) and Shedhorn Sandstone. TENSLEEP SANDSTONE--White to gray sandstone containing thin limestone and dolomite beds. Permian fossils have been found in the topmost beds of the Tensleep at some localities in Washakie Range, Owl Creek Mountains, and southern Bighorn Mountains. AMSDEN FORMATION--Red and green shale and dolomite; at base is brown sandstone.
Pierre Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
PIERRE SHALE (AGE 72 TO 78 Ma)--Dark-gray concretionary marine shale; contains several bentonite beds.
Sedimentary Rocks (Phanerozoic | Mesozoic Cenozoic | Cretaceous-Late Tertiary | Paleocene)
SEDIMENTARY ROCKS--Northern part of Wind River Basin. White-weathering oil-stained sandstone and brown carbonaceous shale.
Sohare Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
SOHARE FORMATION--Lenticular gray and brown sandstone and shale; thin coal beds.
Sohare Formation and Bacon Ridge Sandstone (Phanerozoic | Mesozoic | Cretaceous-Late)
SOHARE FORMATION AND BACON RIDGE SANDSTONE. SOHARE FORMATION (Kso)--Lenticular gray and brown sandstone and shale; thin coal beds. BACON RIDGE SANDSTONE (Kb)--Gray to tan marine sandstone and thick coal beds; gold-bearing quartzite conglomerate in lower part.
Steele Shale (Phanerozoic | Mesozoic | Cretaceous-Late)
STEELE SHALE (AGE ABOUT 78 TO 82 Ma)--Gray soft marine shale containing numerous bentonite beds and thin lenticular sandstone.
Steele Shale and Niobrara Formations (Phanerozoic | Mesozoic | Cretaceous-Late)
STEELE SHALE (Ks) AND NIOBRARA FORMATIONS (Kn). STEELE SHALE (AGE ABOUT 78 TO 82 Ma)--Gray soft marine shale containing numerous bentonite beds and thin lenticular sandstone. NIOBRARA FORMATION (AGE ABOUT 83 Ma)--Light-colored limestone and gray to yellow speckled limy shale.
Sundance and Gypsum Spring Formations (Phanerozoic | Mesozoic | Jurassic-Middle Jurassic-Late)
SUNDANCE (Js) AND GYPSUM SPRING FORMATIONS. SUNDANCE FORMATION--Greenish-gray glauconitic sandstone and shale, underlain by red and gray nonglauconitic sandstone and shale. GYPSUM SPRING FORMATION--Interbedded red shale, dolomite, and gypsum. In north Wyoming wedges out south in T. 39 N.
Sundance and Gypsum Spring Formations and Nugget Sandstone (Phanerozoic | Mesozoic | Triassic(?) Jurassic(?) Jurassic-Early(?) Jurassic-Middle(?) Jurassic-Late)
SUNDANCE AND GYPSUM SPRING FORMATIONS AND NUGGET SANDSTONE. SUNDANCE FORMATION--Greenish-gray glauconitic sandstone and shale, underlain by red and gray nonglauconitic sandstone and shale. GYPSUM SPRING FORMATION--Interbedded red shale, dolomite, and gypsum. In north Wyoming wedges out south in T. 39 N. NUGGET SANDSTONE--gray to dull-red, crossbedded quartz sandstone.
Sundance Formation (Phanerozoic | Mesozoic | Jurassic-Middle Jurassic-Late)
SUNDANCE FORMATION--Greenish-gray glauconitic sandstone and shale, underlain by red and gray nonglauconitic sandstone and shale.
Tensleep Sandstone and Amsden Formation (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late Pennsylvanian(?) Permian)
TENSLEEP SANDSTONE AND AMSDEN FORMATION. North Wyoming: TENSLEEP SANDSTONE--White to gray sandstone containing thin limestone and dolomite beds. Permian fossils have been found in the topmost beds of the Tensleep at some localities in Washakie Range, Owl Creek Mountains, and southern Bighorn Mountains. AMSDEN FORMATION--Red and green shale and dolomite; at base is brown sandstone. South Wyoming: TENSLEEP SANDSTONE AND AMSDEN FORMATION. TENSLEEP SANDSTONE--White to gray sandstone containing thin limestone and dolomite beds. AMSDEN FORMATION--Red and green shale and dolomite; at base is persistent red to brown sandstone.
Wasatch Formation (SW) (Phanerozoic | Cenozoic | Tertiary | Eocene)
WASATCH FORMATION Niland Tongue--Brown sandstone, carbonaceous shale, and coal.
Wells and Amsden Formations (TB), or Casper Formation and Madison Limestone (N, S) (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early Pennsylvanian-Middle(?) Pennsylvanian-Late(?) Permian)
WELLS AND AMSDEN FORMATIONS (Thrust Belt). WELLS FORMATION--Gray limestone interbedded with yellow limy sandstone. AMSDEN FORMATION--Red and gray cherty limestone and shale, sandstone, and conglomerate. CASPER FORMATION AND MADISON LIMESTONE (north, south Wyoming). CASPER FORMATION--Gray, tan, and red thick-bedded sandstone underlain by interbedded sandstone and pink and gray limestone. May include some Devonian(?) sandstone along east flank of Laramie Mountains. MADISON LIMESTONE--Includes Mission Canyon Limestone (blue-gray massive limestone and dolomite), underlain by Lodgepole Limestone (gray cherty limestone and dolomite).