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Geologic units containing silt

Earth material > Unconsolidated material
Silt
A loose aggregate of unlithified mineral or rock particles of silt size (1/256 to 1/16 mm); an unconsolidated deposit consisting essentially of fine-grained clastic particles.
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Alabama
Chilhowee Group undifferentiated (Cambrian)
Chilhowee Group undifferentiated - light to medium-gray arkose, arkosic conglomerate, and discontinous mudstone overlain by greenish-gray mudstone with minor siltstone and sandstone; dominantly light-gray pebbly quartzose sandstone in upper part.
Cochran Formation (Cambrian)
Cochran Formation - poorly sorted arkosic sandstone and conglomerate containing interbedded greenish-gray siltstone and mudstone. The Cochran Formation is exposed only in northeastern Calhoun and northwestern Cleburne 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.
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.
Greensport Formation (Ordovician)
Greensport Formation - variegated dusky-red and dark-yellowish-orange shale, calcareous mudstone, limestone, siltstone, and minor sandstone.
Midway Group; Clayton Formation (Paleocene)
Clayton Formation - (Midway Group), White to yellowsih-gray argillaceous limestone occurs in the upper part (McBryde Limestone Member): the lower part is medium-gray fossiliferous calcareous silt, glauconitic sand and thin beds of sandy limestone and calcareous sandstone (Pine Barren Member). At the base of the formation in southeast AL is a gravelly medium to coarse sand containing clay pebbles. The formation thins west of Wilcox County and westward from Thomaston in eastern Marengo County is mapped with the Porters Creek Formation. The formation is generally deeply weathered and fresh exposures are rare. In western areas exposures consist of weathered white to yellowish-gray argillaceous, fossiliferous sandy limestone, ferruginous sand, and fossiliferous sandstone. In eastern areas exposures consist of residual accumulations of chert boulders, moderate-reddish-orange sand, and clay containing masses and thin layers of iron minerals (limonite-goethite).
Midway Group; Naheola Formation (Paleocene)
Naheola Formation - (Midway Group), The Naheola Formation is restricted to western AL and pinches out in western Butler County. Descriptions of the members of the formation follow in descending order. Coal Bluff Marl Member - glauconitic sand, thin-bedded silty clay, and sandy fossiliferous marl; Oak Hill Member - laminated silt, clay, and fine sand; contains a prominent bed of lignite near the top. The Coal Bluff Marl Member in Sumter County and in parts of Marengo County is mostly cross-bedded fine to coarse sand that is indistinguishable from the overlying lower beds of the Nanafalia Formation. Therefore, in these areas, the contact between the two is mapped at the top of the Oak Hill Member of the Naheola.
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.
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.
Selma Group; Blufftown Formation (Cretaceous)
Blufftown Formation - (Selma Group), The Blufftown extends from the Chattahoochee River Valley westward into central Russell County where it is divided into two westward-extending tongues by an eastward-extending tongue of the Mooreville Chalk. In the Chattahoochee River Valley the Blufftown is mainly glauconitic calcareous fine sand, micaceous clay and marl, fossiliferous clay, gray calcareous fossiliferous sandstone, and carbonaceous clay and silt. To the west the lower tongue of the Blufftown is gravelly sand, glauconitic sand, calcareous clay, and sandy clay and merges with the lower part of the Mooreville Chalk in southwestern Macon County. The upper tongue is mainly calcareous sandy clay and micaceous silty fine sand with thin layers of limestone and sandstone. The upper tongue merges with the Mooreville Chalk and the lower part of the Demopolis Chalk in western Bullock County.
Selma Group; Prairie Bluff Chalk (Upper Cretaceous)
Prairie Bluff Chalk - (Selma Group), Very light-gray to light-bluish-gray firm sandy, fossiliferous brittle chalk and grayish-black silty sandy calcareous glauconitic, fossiliferous clay; semi-indurated beds of sandy, clayey limestone are present in some exposures. Abscent locally in parts of Marengo, Dallas and Wilcox Counties where overlapped by the Clayton Formation or eroded. The Prairie Bluff thins eastward from southwestern Lowndes County to northern Pike County where it interfingers with the Providence Sand.
Selma Group; Providence Sand (Cretaceous)
Providence Sand - (Selma Group), Upper part consists of cross-bedded fine to coarse sand and white, dark-gray and pale-red-purple mottled clay containing lignite, sand, and kaolin; lower part consists of dark-gray laminated to thin-bedded silty clay and abundantly micaceous, carbonaceous, fossiliferous very fine to fine sand. The Providence Sand extends eastward from southeastern Lowndes County into Georgia.
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.
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).
Tuscaloosa Group; Coker Formation (Cretaceous)
Coker Formation - (Tuscaloosa Group), Light-colored micaceous very fine to medium sand, cross-bedded sand, varicolored micaceous clay, and a few thin gravel beds containing quartz and chert pebbles. Beds of thinly laminated finely glauconitic very fine to fine sand, silt and dark-gray carbonaceous clay (Eoline Member) occur locally in the lower part in western AL. Locally quartz and chert gravels at the base of the formation range in size from very fine pebbles to large cobbles. In southeastern Elmore County the formation includes marine sediments consisting of glauconitic, fossiliferous, quartzose fine to medium sand and medium-gray carbonaceous silty clay. Not mapped east of the Tallapoosa River.
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.
Wilcox Group; Hatchetigbee Formation (Eocene)
Hatchetigbee Formation - (Wilcox Group), Light to dark-gray laminated carbonaceous clay, silt and very fine to fine sand, and cross-bedded glauconitic sand; one or more thin beds of fossiliferous marly glauconitic sand and sandstone occur in the upper part. Near the base is a prominent bed of glauconitic calcareous sand containing abundant fossils and spheroidal to pillow-shaped sandstone concretions (Bashi Marl Member). In parts of southeast AL the upper beds of the Th were either eroded or not deposited and the overlying Tt formation directly overlies the Bashi Marl Member.
Wilcox Group; Tuscahoma Sand (Paleocene)
Tuscahoma Sand - (Wilcox Group), Light-gray to light-olive-gray laminated and thin-bedded carbonaceous silt and clay interbedded with fine sand; thin lignite beds occur locally. Lower part of the formation includes beds of fossiliferous, glauconitic fine quartz sand containing speroidal sandstone concretions, gravel and clay pebbles.
Arkansas
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)
Jackson Group (Phanerozoic | Cenozoic | Tertiary | Eocene-Late)
Jackson Group
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
Silt and sand (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Early)
Silt and sand - Contains lenses of gravel and clay
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
Wilcox Group (Phanerozoic | Cenozoic | Tertiary | Eocene-Early)
Wilcox Group
Arizona
Chinle Formation (Late Triassic)
Colorful mudstone, such as in the Painted Desert, and less abundant lenses of sandstone and conglomerate, deposited by a large river system. This unit typically is eroded into badlands topography and contains clays that are prone to shrinking and swelling. (210-230 Ma)
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 Pleistocene to late Miocene basin deposits (Late Pliocene to Early Pleistocene)
Poorly sorted, variably consolidated gravel and sand that range widely in age. These sediments are generally light gray or tan. This unit is generally mapped in areas of deep late Cenozoic stream incision and landscape degradation where thin Quaternary deposits (map units Qy, Qm, Qo) discontinuously blanket older deposits (map units Tsy or Tsm) and the two cannot be differentiated at the scale of this map. (0.75-10 Ma)
Early Pleistocene to latest Pliocene surficial deposits (Late Pliocene to Early Pleistocene)
Coarse relict alluvial fan deposits that form rounded ridges or flat, isolated surfaces that are moderately to deeply incised by streams. These deposits are generally topographically high and have undergone substantial erosion. Deposits are moderately to strongly consolidated, and commonly contain coarser grained sediment than younger deposits in the same area. (0.75-3 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 metavolcanic rocks (Early Proterozoic)
Weakly to strongly metamorphosed volcanic rocks. Protoliths include basalt, andesite, dacite, and rhyolite deposited as lava or tuff, related sedimentary rock, and shallow intrusive rock. These rocks, widely exposed in several belts in central Arizona, include metavolcanic rocks in the Yavapai and Tonto Basin supergroups. (1650 to 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)
Early Tertiary to Late Cretaceous volcanic rocks (Late Cretaceous to Early Tertiary)
Rhyolite to andesite and closely associated sedimentary and near-surface intrusive rocks; commonly dark gray to dark greenish gray or greenish brown. In the ranges west of Tucson, this unit includes thick welded ash-flow tuffs. Volcanic rocks of this unit are inferred to be derived from vents and volcanoes above magma chambers that solidified to form the granitic rocks of map unit TKg. These rocks are restricted to southeastern Arizona except for a small outcrop near Bagdad. (50-82 Ma)
Glen Canyon Group (Early Jurassic)
Conspicuous red, cross-bedded Wingate Sandstone and the conspicuously cross-bedded, eolian, red to buff Navajo Sandstone form prominent cliffs in northern Arizona. These two sandstone units are separated by variably colored siltstone, silty sandstone, and sandstone of the Kayenta and Moenave Formations. (180-210 Ma)
Holocene river alluvium (Holocene)
Unconsolidated to weakly consolidated sand and gravel in river channels and sand, silt, and clay on floodplains. Also includes young terrace deposits fringing floodplains. (0-10 ka)
Holocene surficial deposits (Holocene)
Unconsolidated deposits associated with modern fluvial systems. This unit consists primarily of fine-grained, well-sorted sediment on alluvial plains, but also includes gravelly channel, terrace, and alluvial fan deposits on middle and upper piedmonts. (0-10 ka)
Jurassic sedimentary and volcanic rocks (Jurassic)
Sandstone and conglomerate derived from volcanic rocks with associated intermediate-composition lava flows, breccias, and tuffs. In southern Arizona this unit includes rocks of the Artesa sequence, Pitoikam Formation, Mulberry Wash volcanics, Rudolfo Red Beds, Recreation Red Beds, and Gardner Canyon Formation. In western Arizona it includes the Harquar Formation, rocks of Slumgullion, and related(?) unnamed units in the Kofa and Middle Mountains. This unit is characterized by maroon, brown, and purplish-gray volcanic-lithic sandstone and siltstone, with subordinate to abundant conglomerate, quartz-rich sandstone and sparse limestone. (150-170 Ma)
Late and middle Pleistocene surficial deposits (Middle to Late Pleistocene)
Unconsolidated to weakly consolidated alluvial fan, terrace, and basin-floor deposits with moderate to strong soil development. Fan and terrace deposits are primarily poorly sorted, moderately bedded gravel and sand, and basin-floor deposits are primarily sand, silt, and clay. (10-750 ka)
Middle Miocene to Oligocene sedimentary rocks (Oligocene to Middle Miocene)
Con-glomerate, sandstone, mudstone, limestone, and rock-avalanche breccia (sheet-like deposits of crushed rock) deposited and tilted during widespread normal faulting and basin development. Sediments, mostly conglomerate and sandstone, are commonly medium to dark brown, reddish brown, or brownish gray; younger strata are generally lighter colors. Most deposits are 20 to 30 Ma in southeastern Arizona and 15 to 25 Ma in central and western Arizona. (11-32 Ma)
Middle Miocene to Oligocene volcanic and sedimentary rocks, undivided (Oligocene to Middle Miocene)
Sequences of diverse volcanic rocks with abundant interbedded sedimentary rocks. (11-32 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)
Moenkopi Formation (Early and Middle(?) Triassic)
Dark red sandstone and mudstone; includes gypsum beds in northwestern Arizona; deposited on a low-relief coastal plain. (230-245 Ma)
Morrison Formation (Late Jurassic)
Commonly cliff-forming, cross-bedded sandstone lenses alternating with slope-forming siltstone, mudstone and shale. Colors are highly variable, and include greenish gray, reddish brown, pink, white, and purple. Sands were deposited by braided streams with finer sediment representing overbank or lacustrine deposits. (145-160 Ma)
Oligocene to Paleocene[?] sedimentary rocks (Paleocene(?) to Oligocene)
Light colored, weakly to moderately consolidated conglomerate and sandstone deposited largely or entirely before mid-Tertiary volcanism and extensional faulting. Most sediment was deposited by early Cenozoic streams that flowed northeastward onto the Colorado Plateau from areas to the southwest that are now lower in elevation than the Plateau. Sediments of this map unit, other than the Chuska Sandstone in northeasternmost Arizona, are commonly referred to as "rim gravels" because they now rest on or near the Mogollon Rim, which is the southwestern edge of the Colorado Plateau. (30-65 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)
Pliocene to late Miocene basaltic rocks (Late Miocene to Pliocene)
Mostly dark, inconspicuously flat, low-lying or mesa-forming basalt deposited as lava flows. Rocks included in this unit are located almost entirely in the large volcanic fields south and west of Flagstaff, in smaller fields in northwesternmost Arizona, and in the Hopi Buttes volcanic field on the Navajo and Hopi Indian Reservations north of Holbrook. Original volcanic landforms have been obscured by erosion. (4-8 Ma)
Pliocene to middle Miocene deposits (Middle Miocene to Pliocene)
Moderately to strongly consolidated conglomerate and sandstone deposited in basins during and after late Tertiary faulting. Includes lesser amounts of mudstone, siltstone, limestone, and gypsum. These deposits are generally light gray or tan. They commonly form high rounded hills and ridges in modern basins, and locally form prominent bluffs. Deposits of this unit are widely exposed in the dissected basins of southeastern and central Arizona. (2-16 Ma)
Quaternary surficial deposits, undivided (Quaternary)
Unconsolidated to strongly consolidated alluvial and eolian deposits. This unit includes: coarse, poorly sorted alluvial fan and terrace deposits on middle and upper piedmonts and along large drainages; sand, silt and clay on alluvial plains and playas; and wind-blown sand deposits. (0-2 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)
Shinarump Conglomerate Member, Chinle Formation (Late Triassic)
Basal conglomerate and pebbly sandstone of the Chinle Formation is relatively resistant to erosion and forms extensive benches in some parts of the Colorado Plateau. (210-230 Ma)
California
Carboniferous marine rocks, unit 3 (SE California Clastic Assemblage) (Late Devonian to Early Permian)
Shale, sandstone, conglomerate, limestone, dolomite, chert, hornfels, marble, quartzite; in part pyroclastic rocks
Eocene marine rocks (Paleocene to Oligocene)
Shale, sandstone, conglomerate, and minor limestone; in part Oligocene and Paleocene.
Eocene nonmarine rocks, unit 1 (Northern and Central California) (Eocene)
Sandstone, shale, and conglomerate.
Jurassic marine rocks, unit 1 (Western Sierra Nevada and Western Klamath Mountains) (Triassic to Late Jurassic)
Shale, sandstone, minor conglomerate, chert, slate, limestone; minor pyroclastic rocks
Miocene marine rocks (Oligocene to Pliocene)
Sandstone, shale, siltstone, conglomerate and breccia; in part Pliocene and Oligocene.
Miocene nonmarine rocks (Oligocene to Pleistocene)
Sandstone, shale, conglomerate, and fanglomerate; in part Pliocene and Oligocene.
Oligocene marine rocks (Eocene to Miocene)
Sandstone, shale, and conglomerate; in part Miocene and Eocene.
Oligocene nonmarine rocks, unit 2 (Central and Southern California) (middle Eocene to early Miocene)
Sandstone, shale, and conglomerate; in part Miocene and Eocene.
Pliocene marine rocks (Miocene to Pleistocene)
Sandstone, siltstone, shale, and conglomerate; in part Pleistocene and Miocene.
Plio-Pleistocene and Pliocene loosely consolidated deposits (Miocene to Pleistocene)
Pliocene and/or Pleistocene sandstone, shale, and gravel deposits; in part Miocene.
Tertiary nonmarine rocks, undivided (Paleocene to Pliocene)
Undivided Tertiary sandstone, shale, conglomerate, breccia, and ancient lake deposits.
Upper Cretaceous and Paleocene marine rocks, undivided (Late Cretaceous to Paleocene)
Sandstone, shale, and conglomerate
Colorado
Eolian deposits (Phanerozoic | Cenozoic | Quaternary)
Includes dune sand and silt and Peoria Loess
Older eolian deposits (Phanerozoic | Cenozoic | Quaternary)
Includes Loveland Loess
Sangre de Cristo Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian)
Arkosic conglomerate, sandstone, and siltstone
Connecticut
New Haven Arkose (Upper Triassic; possibly Lower Jurassic at top)
New Haven Arkose - Red, pink, and gray coarse-grained, locally conglomeratic, poorly sorted and indurated arkose, interbedded with brick-red micaceous, locally shaly siltstone and fine-grained feldspathic clayey sandstone.
New Haven Arkose plus Buttress Dolerite (Upper Triassic; possibly Lower Jurassic at top plus Middle? Jurassic)
New Haven Arkose plus Buttress Dolerite - New Haven Arkose - Red, pink, and gray coarse-grained, locally conglomeratic, poorly sorted and indurated arkose, interbedded with brick-red micaceous, locally shaly siltstone and fine-grained feldspathic clayey sandstone. Buttress Dolerite (Middle? Jurassic) - Dark-gray to greenish-gray (weathers brown or gray), medium- to fine-grained, commonly porphyritic, generally massive with well-developed columnar jointing, grading from basalt near contacts to fine-grained gabbro in the interior, composed of plagioclase and pyroxene with accessory opaques and locally devitrified glass, quartz, or olivine.
Stockbridge Marble (Lower Ordovician and Cambrian)
Stockbridge Marble (including Inwood Marble) - White to gray, massive to layered marble, generally dolomitic but containing calcite marble in upper part, locally interlayered with schist or phyllite and with calcareous siltstone or sandstone.
Unit b [of Stockbridge Marble] (Upper and Middle? Cambrian)
Unit b [of Stockbridge Marble] - White, pink, cream, and light-gray, generally well bedded dolomitic marble interlayered with phyllite and schist and with siltstone, sandstone, or quartzite, commonly dolomitic.
Units e and d [of Stockbridge Marble] (Lower Ordovician)
Units e and d [of Stockbridge Marble] - White to gray massive calcite marble, commonly mottled with dolomite and locally interlayered with dolomite marble and calcareous siltstone and sandstone.
Delaware
Bryn Mawr Formation (?)
Bryn Mawr Formation - Red and brown quartz sand with silt, clay and fine gravel.
Chesapeake Group (Tertiary)
Chesapeake Group - Bluish gray silt with quartz sand and some shell beds.
Estuarine deposits (Pleistocene)
Estuarine deposits - mottled, gray and brown, silt and clayey quartz sand
Magothy Formation (Cretaceous)
Magothy Formation - White and buff quartz sand with beds of gray and black clayey silt.
Mt. Laurel-Navesink Formation (Cretaceous)
Mt. Laurel-Navesink Formation - Dark greenish brown and dark gray, highly glauconitic sandy silt and silty sand.
Other nearshore deposits (Pleistocene)
Other nearshore deposits - yellow and gray quartz sand with some interbedded gray silts; chiefly neritic, offshore bar, and lagoonal facies
Potomac Formation (Cretaceous)
Potomac Formation - Variegated silts and clays with beds of quartz sand.
Unit B (Cretaceous-Tertiary)
Unit B - Greenish-gray sandy and clayey glauconitic silt.
Unit C (Tertiary)
Unit C - Grayish-green, clayey glauconitic silt and sand.
Florida
Alluvium (Pleistocene/Holocene)
Alluvium - Undifferentiated Quaternary Sediments - Much of Florida's surface is covered by a varying thickness of undifferentiated sediments consisting of siliciclastics, organics and freshwater carbonates. Where these sediments exceed 20 feet (6.1 meters) thick, they were mapped as discrete units. In an effort to subdivide the undifferentiated sediments, those sediments occurring in flood plains were mapped as alluvial and flood plain deposits (Qal). Sediments showing surficial expression of beach ridges and dunes were mapped separately (Qbd) as were the sediments composing Trail Ridge (Qtr). Terrace sands were not mapped (refer to Healy [1975] for a discussion of the terraces in Florida). The subdivisions of the Undifferentiated Quaternary Sediments (Qu) are not lithostratigraphic units but are utilized in order to facilitate a better understanding of the State's geology. The siliciclastics are light gray, tan, brown to black, unconsolidated to poorly consolidated, clean to clayey, silty, unfossiliferous, variably organic-bearing sands to blue green to olive green, poorly to moderately consolidated, sandy, silty clays. Gravel is occasionally present in the panhandle. Organics occur as plant debris, roots, disseminated organic matrix and beds of peat. Freshwater carbonates, often referred to as marls in the literature, are scattered over much of the State. In southern Florida, freshwater carbonates are nearly ubiquitous in the Everglades. These sediments are buff colored to tan, unconsolidated to poorly consolidated, fossiliferous carbonate muds. Sand, silt and clay may be present in limited quantities. These carbonates often contain organics. The dominant fossils in the freshwater carbonates are mollusks.
Beach ridge and dune (Pleistocene/Holocene)
Beach ridge and dune - Undifferentiated Quaternary Sediments - Much of Florida's surface is covered by a varying thickness of undifferentiated sediments consisting of siliciclastics, organics and freshwater carbonates. Where these sediments exceed 20 feet (6.1 meters) thick, they were mapped as discrete units. In an effort to subdivide the undifferentiated sediments, those sediments occurring in flood plains were mapped as alluvial and flood plain deposits (Qal). Sediments showing surficial expression of beach ridges and dunes were mapped separately (Qbd) as were the sediments composing Trail Ridge (Qtr). Terrace sands were not mapped (refer to Healy [1975] for a discussion of the terraces in Florida). The subdivisions of the Undifferentiated Quaternary Sediments (Qu) are not lithostratigraphic units but are utilized in order to facilitate a better understanding of the State's geology. The siliciclastics are light gray, tan, brown to black, unconsolidated to poorly consolidated, clean to clayey, silty, unfossiliferous, variably organic-bearing sands to blue green to olive green, poorly to moderately consolidated, sandy, silty clays. Gravel is occasionally present in the panhandle. Organics occur as plant debris, roots, disseminated organic matrix and beds of peat. Freshwater carbonates, often referred to as marls in the literature, are scattered over much of the State. In southern Florida, freshwater carbonates are nearly ubiquitous in the Everglades. These sediments are buff colored to tan, unconsolidated to poorly consolidated, fossiliferous carbonate muds. Sand, silt and clay may be present in limited quantities. These carbonates often contain organics. The dominant fossils in the freshwater carbonates are mollusks.
Chattahoochee Formation (Miocene)
Chattahoochee Formation - The Chattahoochee Formation, originally named by Dall and Stanley-Brown (1894), is predominantly a yellowish gray, poorly to moderately indurated, fine-grained, often fossiliferous (molds and casts), silty to finely sandy dolostone (Huddlestun, 1988). Siliciclastic beds and limestones may be present. The Chattahoochee Formation is exposed in Jackson County, central panhandle, on the Chattahoochee "Anticline". It grades laterally across the Gulf Trough into the St. Marks Formation through a broad transition area (Scott, 1986). The Chattahoochee Formation forms the upper part of the FAS in the central panhandle.
Citronelle Formation (Pliocene)
Citronelle Formation - The Citronelle Formation is widespread in the Gulf Coastal Plain. The type section for the Citronelle Formation, named by Matson (1916), is near Citronelle, Alabama. The Citronelle Formation grades laterally, through a broad facies transition, into the Miccosukee Formation of the eastern Florida panhandle. Coe (1979) investigated the Citronelle Formation in portions of the western Florida panhandle. The Citronelle Formation is a siliciclastic, deltaic deposit that is lithologically similar to, and time equivalent with, the Cypresshead Formation and, at least in part, the Long Key Formation (Cunningham et al., 1998) of the peninsula. In the western panhandle, some of the sediments mapped as Citronelle Formation may be reworked Citronelle. The lithologies are the same and there are few fossils present to document a possible younger age. The Citronelle Formation consists of gray to orange, often mottled, unconsolidated to poorly consolidated, very fine to very coarse, poorly sorted, clean to clayey sands. It contains significant amounts of clay, silt and gravel which may occur as beds and lenses and may vary considerably over short distances. Limonite nodules and limonite-cemented beds are common. Marine fossils are rare but fossil pollen, plant remains and occasional vertebrates are found. Much of the Citronelle Formation is highly permeable. It forms the Sand and Gravel Aquifer of the surficial aquifer system.
Hawthorn Group (Miocene)
Hawthorn Group - Undifferentiated Hawthorn Group - The undifferentiated Hawthorn Group occurs at or near the surface near the southern flank of the Ocala Platform from Gilchrist County southward to Pasco County with isolated occurrences in Pinellas County. Correlation of these sediments to the formations of the Hawthorn Group exposed to the east and in the subsurface is uncertain. There is little to no phosphate present in these sediments and fossils are rare. Ages have not been documented but stratigraphic position suggests inclusion in the Hawthorn Group. These sediments may be residual from the weathering and erosion of the Hawthorn Group. The Hawthorn Group sediments on the Brooksville Ridge are deeply weathered and in some outcrops look like Cypresshead Formation siliciclastics. The undifferentiated Hawthorn Group sediments are light olive gray and blue gray in unweathered sections to reddish brown in deeply weathered sections, poorly to moderately consolidated, clayey sands to silty clays and relatively pure clays. These sediments are part of the intermediate confining unit/aquifer system and provide an effective aquitard for the FAS, except where perforated by karst features. Hard-rock phosphate deposits are associated with the undifferentiated Hawthorn Group sediments on the eastern flank of the Brooksville Ridge. The hard rock phosphate deposits were formed by the dissolution of phosphate in the Hawthorn sediments and redeposition in karst features.
Hawthorn Group, Coosawhatchie Formation (Miocene)
Coosawhatchie Formation - The Coosawhatchie Formation is exposed or lies beneath a thin overburden on the eastern flank of the Ocala Platform from southern Columbia County to southern Marion County. Within the outcrop region, the Coosawhatchie Formation varies from a light gray to olive gray, poorly consolidated, variably clayey and phosphatic sand with few fossils, to an olive gray, poorly to moderately consolidated, slightly sandy, silty clay with few to no fossils. Occasionally the sands will contain a dolomitic component and, rarely, the dominant lithology will be dolostone or limestone. Silicified nodules are often present in the Coosawhatchie Formation sediments in the outcrop region. The sediment may contain 20 percent or more phosphate (Scott, 1988). Permeability of the Coosawhatchie sediments is generally low, forming part of the intermediate confining unit/aquifer system.
Hawthorn Group, Peace River Formation, Bone Valley Member (Miocene/Pliocene)
Hawthorn Group, Peace River Formation, Bone Valley Member - The Bone Valley Member (originally the Bone Valley Formation of Matson and Clapp, 1909), Peace River Formation occurs in a limited area on the southern part of the Ocala Platform in Hillsborough, Polk and Hardee Counties. Throughout its extent, the Bone Valley Member is a clastic unit consisting of sand-sized and larger phosphate grains in a matrix of quartz sand, silt and clay. The lithology is highly variable, ranging from sandy, silty, phosphatic clays and relatively pure clays to clayey, phosphatic sands to sandy, clayey phosphorites (Webb and Crissinger, 1983). In general, consolidation is poor and colors range from white, light brown and yellowish gray to olive gray and blue green. Mollusks are found as reworked, often phosphatized casts. Vertebrate fossils occur in many of the beds within the Bone Valley Member. Shark's teeth are often abundant. Silicified corals and wood are occasionally present as well. The Bone Valley Member is an extremely important, unique phosphate deposit and has provided much of the phosphate production in the United States during the twentieth century. Mining of phosphate in the outcrop area began in 1888 (Cathcart, 1985) and continues to the present.
Hawthorn Group, Torreya Formation (Miocene)
Hawthorn Group, Torreya Formation - Torreya Formation - The Torreya Formation is exposed or near the surface from western Gadsden County eastward to western-most Hamilton County. It is informally subdivided into a lower carbonate unit and an upper siliciclastic unit (Scott, 1988). The majority of Torreya Formation outcrops expose the siliciclastic part of the unit. The carbonate sediments are white to light olive gray, generally poorly indurated, variably sandy and clayey, fossiliferous (molds and casts) limestone (mudstone and wackestone). The limestones often grade into calcareous-cemented sands. Phosphate is present in the carbonate sediments, particularly in the Sopchoppy Member. The siliciclastics vary from white to light olive gray, unconsolidated to poorly indurated, slightly clayey sands with minor phosphate to light gray to bluish gray, poorly consolidated, variably silty clay (Dogtown Member). The siliciclastics are sporadically fossiliferous. The Torreya Formation overlies the FAS and forms part of the intermediate confining unit/aquifer system.
Trail Ridge sands (Pleistocene)
Trail Ridge Sands - Undifferentiated sediments - Undifferentiated Quaternary Sediments - Much of Florida's surface is covered by a varying thickness of undifferentiated sediments consisting of siliciclastics, organics and freshwater carbonates. Where these sediments exceed 20 feet (6.1 meters) thick, they were mapped as discrete units. In an effort to subdivide the undifferentiated sediments, those sediments occurring in flood plains were mapped as alluvial and flood plain deposits (Qal). Sediments showing surficial expression of beach ridges and dunes were mapped separately (Qbd) as were the sediments composing Trail Ridge (Qtr). Terrace sands were not mapped (refer to Healy [1975] for a discussion of the terraces in Florida). The subdivisions of the Undifferentiated Quaternary Sediments (Qu) are not lithostratigraphic units but are utilized in order to facilitate a better understanding of the State's geology. The siliciclastics are light gray, tan, brown to black, unconsolidated to poorly consolidated, clean to clayey, silty, unfossiliferous, variably organic-bearing sands to blue green to olive green, poorly to moderately consolidated, sandy, silty clays. Gravel is occasionally present in the panhandle. Organics occur as plant debris, roots, disseminated organic matrix and beds of peat. Freshwater carbonates, often referred to as marls in the literature, are scattered over much of the State. In southern Florida, freshwater carbonates are nearly ubiquitous in the Everglades. These sediments are buff colored to tan, unconsolidated to poorly consolidated, fossiliferous carbonate muds. Sand, silt and clay may be present in limited quantities. These carbonates often contain organics. The dominant fossils in the freshwater carbonates are mollusks.
Undifferentiated sediments (Pleistocene/Holocene)
Undifferentiated sediments - Undifferentiated Quaternary Sediments - Much of Florida's surface is covered by a varying thickness of undifferentiated sediments consisting of siliciclastics, organics and freshwater carbonates. Where these sediments exceed 20 feet (6.1 meters) thick, they were mapped as discrete units. In an effort to subdivide the undifferentiated sediments, those sediments occurring in flood plains were mapped as alluvial and flood plain deposits (Qal). Sediments showing surficial expression of beach ridges and dunes were mapped separately (Qbd) as were the sediments composing Trail Ridge (Qtr). Terrace sands were not mapped (refer to Healy [1975] for a discussion of the terraces in Florida). The subdivisions of the Undifferentiated Quaternary Sediments (Qu) are not lithostratigraphic units but are utilized in order to facilitate a better understanding of the State's geology. The siliciclastics are light gray, tan, brown to black, unconsolidated to poorly consolidated, clean to clayey, silty, unfossiliferous, variably organic-bearing sands to blue green to olive green, poorly to moderately consolidated, sandy, silty clays. Gravel is occasionally present in the panhandle. Organics occur as plant debris, roots, disseminated organic matrix and beds of peat. Freshwater carbonates, often referred to as marls in the literature, are scattered over much of the State. In southern Florida, freshwater carbonates are nearly ubiquitous in the Everglades. These sediments are buff colored to tan, unconsolidated to poorly consolidated, fossiliferous carbonate muds. Sand, silt and clay may be present in limited quantities. These carbonates often contain organics. The dominant fossils in the freshwater carbonates are mollusks.
Georgia
Cusseta Sand (Cretaceous)
Cusseta Sand
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.
Kinderhook Series (Phanerozoic | Paleozoic | Carboniferous Mississippian-Early)
Gilmore City Limestone- light gray fossiliferous limestone, commonly oolitic. Approx thickness 155 ft. Hampton Formation- limestone and dolomite; fossiliferous gray chert in lower portion. Approx. thickness 150 ft. Starrs Cave Formation- bio-fragmental limestone; oolitic in part. Approx thickness 15 ft. Prospect Hill Formation- greenish-gray siltstone. Approx thickness 90 ft. McCraney Limestone- very pale orange to pale yellowish-brown sublithographic limestone and brown dolomite. Approx thickness 65 ft.
Wabaunsee Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgil])
Cyclic deposits, principally shale with limestone, siltstone, minor sandstone units and thin coal seams.
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, 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.
Basalt and silt; Late Pleistocene basalt flows and interlayered lacustrine silt beds of subunit 1b; Snake River Plain (Late Pleistocene)
Upper Pleistocene Snake Plain basaltic lava flows, unit 1.
Black argillite, quartzite, siltite, marble, chert, and syngenetic silver-lead-zinc deposits; Devonian euxinic marine-basin deposits; central Idaho (Devonian)
Devonian thrusted, deep-water siliceous argillite and quartzite of central Idaho.
Clay, silt, sand, and gravel; Late Pleistocene glacial-lake sediments; Basin and Range province (Late Pleistocene)
Pleistocene glacial-lake, ponded-water, and shoreline sediments.
Conglomerate, sandstone, and siltstone; Eocene to Late Cretaceous alluvial-fan deposits; east-central Idaho, Cordilleran fold-thrust belt, piggyback basins (Eocene to Late Cretaceous )
Lower Tertiary to Upper Mesozoic breccia, conglomerate and sandstone; syntectonic in part.
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, siltstone, arenite, and chert; Devonian and Silurian marine upper continental-slope deposits; east-central and central Idaho; (Devonian and Silurian)
Devonian and Silurian shallow-water marine carbonate units of east-central Idaho.
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.
Gravel; Early Pleistocene alluvium; western Snake River Plain (Pleistocene)
Lower Pleistocene deposits; outwash, fanglomerate, flood and terrace gravels.
Gravel, sand, and clay; Quaternary-Tertiary colluvium and fanglomerate; western Idaho (Pleistocene and Pliocene)
Pleistocene and Pliocene fanglomerate, colluvium, and poorly sorted gravel deposits.
Gravel, sand, silt, clay; Late Pleistocene glacio-alluvial and lacustrine deposits; Basin and Range, and Snake River Plain (Late Pleistocene)
Upper Pleistocene deposits; outwash, fanglomerate, flood and terrace gravels.
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, sandstone, siltstone, and chert; Lower Permian to Lower Pennsylvanian marine continental-shelf deposits; east-central Idaho (Early Permian to Early Pennsylvanian)
Lower Permian to Lower Pennsylvanian (Carboniferous) shallow-water detritus.
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, 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.
Meta-conglomerate mafic metavolcanic rocks, siltite, argillite, and limestone; Late Proterozoic rifted continental margin; northwestern Idaho (Late Proterozoic)
Younger Precambrian mafic volcanic flows and conglomerates of northern Idaho.
Quartzite, argillite, carbonate, meta-conglomerate, siltite, intermediate volcanic rock; Late Proterozoic rifted continental margin; southeastern Idaho (Late Proterozoic)
Younger Precambrian detrital units of central and southeastern Idaho; subdivisions are (Z2s and Z1s).
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, 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.
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.
Silt, clay, and diatomite; Middle Pleistocene lacustrine sediments of lava-dammed lakes; western Snake River Plain (Middle Pleistocene)
Middle Pleistocene lava-dammed Snake Plain lake beds of silt, clay and diatomite.
Silt, clay, sand, and gravel; Quaternary-Tertiary alluvial and lacustrine deposits; western Snake River Plain (Early Pleistocene and Late Pliocene)
Pleistocene and Pliocene stream and lake deposits.
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).
Tuff, arkose, claystone, siltstone, conglomerate, lignite; Miocene alluvial and lacustrine deposits (Miocene)
Miocene stream and lake deposits; generally associated with volcanic episodes.
Illinois
Cambrian (Cambrian)
Cambrian
Cretaceous (Cretaceous)
Cretaceous
Kinderhookian Series (Mississippian)
Kinderhookian Series
Maquoketa Group (Ordovician)
Maquoketa Group
Tertiary - Paleocene, Eocene (Tertiary)
Tertiary - Paleocene, Eocene
Kansas
Alluvium (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
unconsolidated sand, silt, clay, and gravel
Alluvium (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
unconsolidated sand, silt, clay, and gravel
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.
Drift (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
sand, silt, clay, and some gravel
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.
Loess (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
eolian silts
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
Kentucky
Alluvium (Pleistocene to Holocene)
Alluvium; includes glacial deposits along the Ohio River and its tributaries west of Cannelton locks
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, middle part (Pennsylvanian)
Breathitt Formation, middle part
Garrard Siltstone and Kope and Clays Ferry Formations, undivided (Ordovician)
Garrard Siltstone and Kope and Clays Ferry Formations, undivided
Lee Formation (Mississippian to Pennsylvanian )
Lee Formation
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
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
Louisiana
Braided Stream Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray, tan and brown fine to coarse sand; some clay silt and gravel. Overlain by 1-9 meters of loess.
Braided Stream Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray, tan and brown fine to coarse sand; some clay silt and gravel.
Cane River Formation (Phanerozoic | Cenozoic | Tertiary | Eocene)
brown silty clay with basal glauconitic, fossiliferous silts which may weather to ironstone locally.
Castor Creek Member (Phanerozoic | Cenozoic | Tertiary | Miocene)
gray to dark gray calcareous clays which may weather to black soil; lignitic clays and noncalcreous clayey silts
Chenier Plain, Fresh Marsh (Phanerozoic | Cenozoic | Quaternary | Holocene)
gray to brown to black clay and silt of high organic content.
Chenier Plain, Saline Marsh (Phanerozoic | Cenozoic | Quaternary | Holocene)
gray to brown to black clay and silt of moderate organic content.
Cockfield Formation (Phanerozoic | Cenozoic | Tertiary | Eocene)
brown lignitic clays, silts and sands; some sideritic glauconite may weather to brown ironstone in lower part.
Dough Hills Member (Phanerozoic | Cenozoic | Tertiary | Miocene)
gray to yellow silty clays; light gray calcareous clays which may weather to black soil; some siliceous silt and volcanic ash beds.
High Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
tan to orange clay, silt, and sand with a large amount of basal gravels. Overlain by 1-9 meters of loess.
High Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
tan to orange clay, silt, and sand with a large amount of basal gravels.
Intermediate Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally. Overlain by 1-9 meters of loess.
Intermediate Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to orange-brown clay, sandy clay, and silt; much sand and gravel locally.
Natural Levees (Phanerozoic | Cenozoic | Quaternary | Holocene)
gray and brown silt, silty clay, some very fine sand, reddish brown along the Red River.
Prairie Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to light brown clay, sandy clay, silt, sand, and some gravels. Overlain by 1-9 meters of loess.
Prairie Terraces (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
light gray to light brown clay, sandy clay, silt, sand, and some gravels.
Williamson Creek Member (Phanerozoic | Cenozoic | Tertiary | Miocene)
white to gray silts, siltstones, silty clays, and sand beds; some lenses of black chert gravel.
Massachusetts
Cretaceous sediments (Cretaceous)
Cretaceous sediments - Clay, silt, sand, and gravel, mostly of non-marine and nearshore marine origin, Campanian and older.
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.
Red arkosic conglomerate, sandstone, and siltstone (Upper Triassic)
Red arkosic conglomerate, sandstone, and siltstone - In Essex County.
Roxbury Conglomerate (Proterozoic Z to earliest Paleozoic)
Roxbury Conglomerate - Conglomerate, sandstone, siltstone, argillite, and melaphyre. Consists of Brookline, Dorchester, and Squantum Members. Roxbury Conglomerate forms base of Boston Bay Group. Divided into Brookline, Dorchester, and Squantum Members. Conglomerate in Brookline Member contains clasts of Dedham Granite, quartzite (possibly from Westboro Formation), and volcanic rock from underlying Mattapan Volcanic Complex. Dorchester Member consists of interbedded argillite and sandstone and forms an intermediate unit between Brookline Member and overlying Cambridge Argillite. Uppermost Squantum Member is a distinctive diamictite which appears to pinch out in northern part of basin. Brighton Melaphyre lies within Brookline Member and consists of mafic volcanic rocks (quartz keratophyre, keratophyre, and spilite). Roxbury clearly lies nonconformably on Dedham Granite near Hull, MA; can be traced continuously over Mattapan Volcanic Complex. Age is Proterozoic Z and possibly Early Cambrian (Goldsmith, 1991).
Sugarloaf Formation (Lower Jurassic)
Sugarloaf Formation - Reddish-brown to pale red arkose, and gray sandstone, gray siltstone, and black shale interpreted as lake beds.
Tertiary sediments (Tertiary)
Tertiary sediments - Unconsolidated sand, silt, and clay in discontinuous patches; contains Tertiary fossils; may include Pleistocene sediments (cross section only).
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
Chesapeake Group; Choptank Formation (Miocene)
Chesapeake Group; Choptank Formation - Interbedded brown to yellow very fine-grained to fine-grained sand and gray to dark bluish-green argillaceous silt; locally indurated to calcareous sandstone; prominent shell beds; thickness 0 to 50 feet.
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.
Gettysburg Shale (Triassic)
Gettysburg Shale - Red shale and soft red sandstone and siltstone; estimated thickness less than 5,000 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.
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.
Lowland Deposits (Quaternary)
Lowland Deposits - Gravel, sand, silt, and clay. Medium- to coarse-grained sand and gravel; cobbles and boulders near base; commonly contains reworked Eocene glauconite; varicolored silts and clays; brown to dark gray lignitic silty clay; contains estuarine to marine fauna in some areas (includes in part Pamlico, Talbot, Wicomico and Sunderland Formations of earlier reports); thickness 0 to 150 feet.
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.
Matawan Formation (Cretaceous)
Matawan Formation - Dark gray micaceous, glauconitic, argillaceous, fine-grained sand and silt; absent in outcrop southwest of Patuxent River; thickness 0 to 70 feet.
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.
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.
Potomac Group, including Raritan and Patapsco Formations, Arundel Clay, and Patuxent Formation (Cretaceous)
Potomac Group - Interbedded quartzose gravels; protoquartzitic to orthoquartzitic argillaceous sands; and white, dark gray, and multicolored silts and clays; thickness 0 to 800 feet. Includes Raritan and Patapsco Formations - Gray, brown, and red variegated silts and clays; lenticular, cross-bedded, argillaceous, subrounded sands; minor gravels; thickness 0 to 400 feet; Arundel Clay - Dark gray and maroon lignitic clays; abundant siderite concretions; present only in Baltimore-Washington area; thickness 0 to 100 feet; and Patuxent Formation - White or light gray to orange-brown, moderately sorted, cross-bedded, argillaceous, angular sands and subrounded quartz gravels; silts and clays subordinate, predominantly pale gray; thickness 0 to 250 feet.
Quaternary Deposits Undivided (Quaternary)
Quaternary Deposits Undivided - Undifferentiated gray to buff sand and gravel, gray to brown lignitic silt and clay, occasional boulders, and rare shell beds. Surficial deposits occur as intercalated fluvial sands and marsh muds (e.g. in upstream floodplain of the Wicomico and Nanticoke Rivers), well-sorted, stablized dune sands (e.g. eastern Wicomico County), shell-bearing estuarine clays and silts (e.g. lower Dorchester County) and Pocomoke River basin of Worcester County), and beach zone sands (e.g. Fenwick and Assateague Islands). Wisconsin to Holocene in age. Subsurface deposits of pre-Wisconsin age consist of buff to reddish-brown sand and gravel locally incised into Miocene sediments (e.g. Salisbury area), estuarine to marine white to gray sands, and gray to blue, shell-bearing clays (e.g. Worcester County).
Upland Deposits (Eastern Shore) (Quaternary)
Upland Deposits (Eastern Shore) - Gravel, sand, silt, and clay. Mostly cross-bedded, poorly sorted, medium- to coarse-grained white to red sand and gravel; boulders near base; minor pink and yellow silts and clays; (Wicomico Formation of earlier reports); thickness 0 to 90 feet, locally thicker in paleochannels.
Upland Deposits (Western Shore) (Quaternary)
Upland Deposits (Western Shore) - Gravel and sand, commonly orange-brown, locally limonite-cemented; minor silt and red, white, or gray clay; (includes Brandywine, Bryn Mawr, and Sunderland Formations of earlier reports); lower gravel member and upper loam member in Southern Maryland; thickness 0 to 50 feet.
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.
Maine
Devonian Tarratine Formation (Devonian)
Devonian Tarratine Formation
Ordovician - Cambrian Aziscohos Formation (Ordovician - Cambrian)
Ordovician - Cambrian Aziscohos Formation
Ordovician - Cambrian Chase Brook Formation (Ordovician - Cambrian)
Ordovician - Cambrian Chase Brook Formation
Ordovician Chandler Ridge Formation (Ordovician)
Ordovician Chandler Ridge Formation
Precambrian Z rocks of Islesboro (Precambrian Z)
Precambrian Z rocks of Islesboro
Silurian - Ordovician Aroostook River Formation (Silurian - Ordovician)
Silurian - Ordovician Aroostook River Formation
Michigan
Coldwater Shale (Mississippian)
Coldwater Shale
Menominee Group; Composite unit of Siamo Slate and Ajibik Quartzite (Early Proterozoic)
Menominee Group; Composite unit of Siamo Slate and Ajibik Quartzite - Siamo Slate is laminated green siltstone and argillite. Ajibik Quartzite is white, buff, and pink orthoquartzite and less abundant sericite quartzite.
Minnesota
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
North Range Group; Mahnomen Formation (Early Proterozoic)
North Range Group; Mahnomen Formation - Claystone, shale, siltstone, and graywacke metamorphosed to the greenschist facies
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
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
HOLOCENE SERIES (Phanerozoic | Cenozoic | Quaternary | Holocene)
HOLOCENE SERIES - Alluvium - clay, silt, sand, and gravel
JOACHIM DOLOMITE, DUTCHTOWN FORMATION (Phanerozoic | Paleozoic | Ordovician-Middle [Mohawkian])
JOACHIM DOLOMITE, DUTCHTOWN FORMATION
PLEISTOCENE SERIES (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
PLEISTOCENE SERIES - Loess, till, drift, clay, silt, sand and gravel (shown on cross section, not on map)
SHAWNEE GROUP (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Upper Virgilian])
SHAWNEE GROUP - cyclic deposits, limestone and shale with sandstone and siltstone.
Mississippi
Pascagoula and Hattiesburg formation (Miocene)
Pascagoula and Hattiesburg formation - Green and bluish-green clay, sandy clay, and sand; gray siltstone and sand; locally fossiliferous.
Montana
Flaxville gravel (Phanerozoic | Cenozoic | Tertiary)
Flaxville gravel: Brown, yellow, and gray gravel, sand, and silt with marl and volcanic ash locally.
North Carolina
Beaufort Formation, Undivided (Tertiary)
Beaufort Formation, Undivided - Unnamed upper member: sand and silty clay, glauconitic, fossiliferous, and locally calcareous. Jericho Run Member: siliceous mudstone with sandstone lenses, thin bedded; basal phosphatic pebble conglomerate.
Chilhowee Group; Lower Chilhowee (Cambrian)
Lower Chilhowee - feldspathic arenite, white to yellowish gray. Minor silty shale, feldspathic siltstone, and conglomerate in lower part. Includes Unicoi Formation of Hot Springs window.
Waccamaw Formation (Tertiary)
Waccamaw Formation - fossiliferous sand with silt and clay, bluish-gray to tan, loosely consolidated. Straddles Pleistocene-Pliocene boundary.
North Dakota
Bullion Creek Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene)
Yellow-brown silt, sand, clay, sandstone, and lignite; river, lake, and swamp sediment; as thick as 200 meters (600 feet).
Coleharbor Formation- Offshore Sediment- Eroded Lake Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Laminated silt and clay of glacier-dammed lakes; as thick as 60 meters (200 feet). Flat-bedded sediment along valley sides exposed as a result of postdepositional erosion.
Coleharbor Formation- Offshore Sediment- Ice-Walled Lake Sediment or Collapsed Supraglacial-Lake Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Laminated silt and clay of glacier-dammed lakes; as thick as 60 meters (200 feet). Flat-bedded sediment elevated above surrounding area or floded sediment with hummocky topography.
Coleharbor Formation- Offshore Sediment- Proglacial Lake Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Laminated silt and clay of glacier-dammed lakes; as thick as 60 meters (200 feet). Flat-bedded sediment of low-lying plains
Glacial Sediment- Collapsed/Draped Transition Sediments (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Collapsed Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Glacial Sediment Draped Over Pre-existing Topography (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment-Glacial Sediment Draped Over Pre-existing Topography (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Glacial Sediment on Subglacially Molded Surfaces (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Glacial Sediment on Thrust Masses (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- River-Eroded Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Slopwash-Eroded Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Glacial Sediment- Wave-Eroded Glacial Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Unbedded, unsorted mixture of clay, silt, sand, and pebbles, and a few cobbles and boulders; as thick as 30 meters (100 feet)
Golden Valley Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene)
Upper member: Yellow-brown micaceous sandstone, sand, silt, and clay; fluvial sediment; as thick as 60 meters (200 feet). Lower member: White or yellow clay, silt, and sand; a weatering zone developed on underlying unit; as thick as 20 meters (65 feet).
Hell Creek Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Gray sand, silt, clay, and sandstone; river sediment; as thick as 150 meters (500 feet).
Ludlow Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene)
Gray-brown and yellow-brown silt, sand, clay and sandstone, and lignite; river, lake, and swamp sediment; as thick as 100 meters (300 feet).
Oahe Formation- Pond Sediment (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Dark, obscurely bedded clay and silt; typically a few meters thick; in modern ephemeral ponds.
Oahe Formation- River Sediment (Phanerozoic | Cenozoic | Quaternary | Holocene)
Dark, obscurely bedded clay and silt (overbank sediment); generally overlying cross-bedded sand (channel sediment); as thick as ten meters (30 feet); on flood plains of modern streams.
Oahe Formation- Windblown Silt (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Obscurely bedded silt with paleosols; as thick as 6 meters (20 feet) where mapped. As much as 2 meters (7 feet) of windblown silt is present, but not mapped, on many level uplands southwest of the Missouri River, and less than 1 meter (3 feet) occurs at the surface throughout the state.
Sentinel Butte Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene)
Gray-brown silt, sand, clay, sandstone, and lignite; river, lake, and swamp sediment; as thick as 200 meters (600 feet).
Slope Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene)
Gray-brown and yellow-brown silt, sand, clay, sandstone, and lignite; river, lake, and swamp sediment; as thick as 100 meters (300 feet).
Nebraska
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.
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.
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
White River Group (Phanerozoic | Cenozoic | Tertiary | Oligocene)
Clay, some claystone, silt and siltstone. Predominantly greenish gray and volcaniclastic. Other occurrences are greenish gray to white and bentonitic. Local channel sandstone at base. Aprox thickness 195 ft.
New Hampshire
Fitch and Clough Formations, undivided (Silurian)
Fitch and Clough Formations, undivided.
New Jersey
Belleplain Member of the Kirkwood Formation (middle Miocene, Serravallian)
Belleplain Member - Clay to silty clay at the base and sand at the top. Clay, massive to laminated, gray-brown, locally contains abundant diatoms and scattered small shell fragments. Sand, fine- to medium-grained, pale-gray to white, somewhat micaceous and woody with scattered shell fragments. Most Belleplain sand is quartz with lesser amounts of feldspar and mica. Pyrite is common in clayey strata. The Belleplain subcrops beneath surficial deposits where the overlying Cohansey Formation was eroded away. Along the Atlantic Ocean, the member is exposed on the southern sheet between Beach Haven Terrace, Ocean County, and Brigantine, Atlantic County, where the unit is overlain by thin to thick deposits of alluvium. The member is as much as 15 m (49 ft) thick. The basal contact with the underlying Wildwood Member is sharp and unconformable with a thin bed of reworked coarse-grained quartz sand at the base. A middle Miocene age for the Belleplain was determined from diatoms. Specifics of the diatom biostratigraphy are discussed in the Description of Subsurface Units. Shells from this unit had a strontium-isotope age estimate of 13.2 Ma (Sugarman and others, 1993).
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.
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.
Cheesequake Formation (Upper Cretaceous, lower Campanian and upper Santonian)
Cheesequake Formation - New unit named herein for outcrops in gullies at Cheesequake in the eastern part of the South Amboy 7.5-min quadrangle. Basal sand, quartz and glauconite, fine-grained, clayey, thin-bedded, dark-greenish-gray; middle part, quartz sand, very fine grained, thick-bedded, dark-gray, micaceous, and clayey silt with scattered and varying amounts of glauconite sand; upper part, quartz sand, fine-grained, clayey, thinbedded. Sand, excluding glauconite sand beds, is primarily quartz with small amounts of feldspar and mica. In most areas, particularly in the updip sections, the upper sand has been eroded away. This formation underlies most of the map area and is as much as 43 m (141 ft) thick. Nannofossils obtained from the Toms River and Freehold drillholes indicate that the Cheesequake Formation is latest Santonian at the base to earliest Campanian at the top (P.C. Valentine, oral commun., 1989) or equivalent to Zones CC16 to CC17. Thus the Santonian-Campanian boundary lies within the Cheesequake Formation. Studies of pollen (Litwin and others, 1993) in outcrop indicate a pollen assemblage containing elements of the ?Pseudoplicapollis cuneata-Semioculopollis verrucosa Zone (Vc of Christopher, 1982) and the CA2 Zone of Wolfe (1976).
Cheesequake Formation (Upper Cretaceous, lower Campanian and upper Santonian)
Cheesequake Formation - Clay and clay-silt, micaceous, thin-bedded to laminated, dark-gray; weathers light tan. Contains abundant wood fragments intercalated with light-colored, fine-grained micaceous quartz sand and is rarely crossbedded. Rock fragments and feldspar are minor sand constituents. Small cylindrical burrows occur in the updip area. Abundant, rounded, pale-gray siderite concretions (about 8 cm (3 in) in diameter) occur in thin discontinuous beds. Sand interfingers rapidly within a short distance with extensively bioturbated, dark-gray, very micaceous, somewhat woody clay-silt. The basal clay-silt has extensive cylindrical burrows filled with fine-grained, light- to medium-green botryoidal glauconite. The basal contact with the underlying Magothy Formation is sharp. Reworked siderite concretions and some glauconite and coarse-grained quartz sand are found along the contact within the Cheesequake. Unit exposed only in the South Amboy and Keyport quadrangles. The unit is about 14 m (46 ft) thick. The age of the Cheesequake was determined from pollen (Litwin and others, 1993), which indicates the unit is between the Merchantville Formation microflora (CA2 Zone of Wolfe, 1976, lower Campanian) and the uppermost Magothy microflora (?Pseudoplicapollis cunceata-Semioculopollis verrucosa Zone of Christopher, 1979, upper Santonian). It is probable that the Cheesequake Formation contains the Santonian-Campanian boundary. This unit was not recognized by Petters (1976) who concluded that the Magothy and Merchantville interfingered in the subsurface and the Merchantville was, in part, Santonian.
Feltville Formation Conglomerate and Sandstone facies (Lower Jurassic)
Feltville Formation Conglomerate and Sandstone facies - Near Oakland, subrounded pebbles to cobbles of quartzite and quartz in a red siltstone and sandstone matrix (Jfc) interfinger with sandstone and siltstone of the Feltville Formation.
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 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 (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.
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).
Lockatong Formation (Upper Triassic)
Lockatong Formation - Predominantly cyclic lacustrine sequences of silty, dolomitic or analcime-bearing argillite; laminated mudstone; silty to calcareous, argillaceous very fine grained sandstone and pyritic siltstone; and minor silty limestone, mostly light- to dark-gray, greenishgray, and black. Grayish-red, grayish-purple, and dark-brownish-red sequences (Trlr) occur in some places, especially in upper half. Two types of cycles are recognized: freshwater-lake (detrital) and alkaline-lake (chemical) cycles. Freshwater-lake cycles average 5.2 m (17 ft) thick. They consist of basal, transgressive, fluvial to lake-margin deposits that are argillaceous, very fine grained sandstone to coarse siltstone with indistinct lamination, planar or cross lamination, or are disrupted by convolute bedding, desiccation cracks, root casts, soil-ped casts, and tubes. Medial lake-bottom deposits are laminated siltstones, silty mudstones, or silty limestones that are dark gray to black with calcite laminae and grains and lenses, or streaks of pyrite; fossils are common, including fish scales and articulated fish, conchostracans, plants, spores, and pollen. Upper regressive lake margin, playa lake, and mudflat deposits are light- to dark-gray silty mudstone to argillitic siltstone or very fine grained sandstone, mostly thick bedded to massive, with desiccation cracks, intraformational breccias, faint wavy laminations, burrows, euhedral pyrite grains, and dolomite or calcite specks. Alkaline-lake cycles are similar to freshwater-lake cycles, but are thinner, averaging 3 m (10 ft), have fewer fossils (mainly conchostracans), and commonly have red beds, extensive desiccation features, and abundant analcime and dolomite specks in the upper parts of cycles. Thickness near Byram is about 1,070 m (3,510 ft). The formation thins to the southeast and northeast; thickness near Princeton is less than 700 m (2,297 ft).
Lockatong Formation (Upper Triassic)
Lockatong Formation (Kummel, 1897) - Cyclically-deposited sequences consisting of light- to dark-gray, greenish-gray, and black, dolomitic or analcime-bearing silty argillite, laminated mudstone, silty to calcareous, argillaceous, very-fine-grained pyritic sandstone and siltstone, and minor silty limestone (Trl). Grayish-red, grayish-purple, and dark-brownish-red sequences (Trlr) common in upper half. Two types of cycles are recognized: detrital and chemical. Detrital cycles average 5.2 m (17 ft) thick and consist of basal, argillaceous, very fine grained sandstone to coarse siltstone; medial, dark-gray to black, laminated siltstone, silty mudstone, or silty limestone; and upper, light- to dark-gray, silty to dolomitic or analcime-rich mudstone, argillitic siltstone, or very-fine-grained sandstone. Chemical cycles are similar to detrital cycles, but thinner, averaging 3.2 m (10.5 ft). Cycles in northern Newark basin are thinner and have arkosic sandstone in lower and upper parts. Upper part of formation in northern basin composed mostly of light-gray to light-pinkish-gray or light-brown, coarse- to fine-grained, thick- to massive-bedded arkosic sandstone (Trla). Thermally metamorphosed into hornfels where intruded by diabase (Jd). Interfingers laterally and gradationally with quartz sandstone and conglomerate (Trls) and quartzite conglomerate (Trlcq) near Triassic border fault in southwestern area of map. Maximum thickness of Lockatong Formation about 1,070 m (3,510 ft).
Lockatong Formation red bed (Upper Triassic)
Lockatong Formation red bed - Predominantly cyclic lacustrine sequences of silty, dolomitic or analcime-bearing argillite; laminated mudstone; silty to calcareous, argillaceous very fine grained sandstone and pyritic siltstone; and minor silty limestone, mostly light- to dark-gray, greenishgray, and black. Grayish-red, grayish-purple, and dark-brownish-red sequences (Trlr) occur in some places, especially in upper half. Two types of cycles are recognized: freshwater-lake (detrital) and alkaline-lake (chemical) cycles. Freshwater-lake cycles average 5.2 m (17 ft) thick. They consist of basal, transgressive, fluvial to lake-margin deposits that are argillaceous, very fine grained sandstone to coarse siltstone with indistinct lamination, planar or cross lamination, or are disrupted by convolute bedding, desiccation cracks, root casts, soil-ped casts, and tubes. Medial lake-bottom deposits are laminated siltstones, silty mudstones, or silty limestones that are dark gray to black with calcite laminae and grains and lenses, or streaks of pyrite; fossils are common, including fish scales and articulated fish, conchostracans, plants, spores, and pollen. Upper regressive lake margin, playa lake, and mudflat deposits are light- to dark-gray silty mudstone to argillitic siltstone or very fine grained sandstone, mostly thick bedded to massive, with desiccation cracks, intraformational breccias, faint wavy laminations, burrows, euhedral pyrite grains, and dolomite or calcite specks. Alkaline-lake cycles are similar to freshwater-lake cycles, but are thinner, averaging 3 m (10 ft), have fewer fossils (mainly conchostracans), and commonly have red beds, extensive desiccation features, and abundant analcime and dolomite specks in the upper parts of cycles. Thickness near Byram is about 1,070 m (3,510 ft). The formation thins to the southeast and northeast; thickness near Princeton is less than 700 m (2,297 ft).
Lockatong Formation red bed (Upper Triassic)
Lockatong Formation red bed - Cyclically-deposited sequences consisting of light- to dark-gray, greenish-gray, and black, dolomitic or analcime-bearing silty argillite, laminated mudstone, silty to calcareous, argillaceous, very-fine-grained pyritic sandstone and siltstone, and minor silty limestone (Trl). Grayish-red, grayish-purple, and dark-brownish-red sequences (Trlr) common in upper half.
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.
Lower Member of the Kirkwood Formation (lower Miocene, Aquitanian)
Lower Member - Complex unit in which facies changes are common. In outcrop, some of the lower member is a light-colored quartz sand (Grenloch facies of Isphording, 1970). The facies pinches out rapidly in the subsurface, and the unit is primarily a massive to finely laminated, dark-gray clay (Alloway clay of Kummel and Knapp, 1904). This clay facies occurs as far south as Clayton, Gloucester County, where the lower part changes to a fossiliferous clayey silt. The lower clayey facies thickens to over 30 m (98 ft) in the coastal region. Here, the lower facies is mostly dark-gray clayey silt that is locally very fossiliferous. The unit varies in thickness but is thickest, as much as 80 m (262 ft), in the southeastern part of the central sheet. South of Bridgeton, Cumberland County, sand is present at the top of the member. This sand thickens to over 23 m (75 ft) at the coast where it is part of the "800 foot" sand, the principal aquifer in the coastal region. Quartz and siliceous rock fragments are the major sand minerals. Feldspars typically constitute less than 10 percent of the sand fraction except in the reworked beds where they make up as much as 25 percent of the sand. Mica and wood fragments are minor constituents. The basal contact with the underlying unit is sharp and unconformable. Commonly there is a 0.3- to 1-m (1- to 3-ft)-thick zone along this contact in which coarse-grained quartz sand and some gravel are present. Because of the quartz sand in the lower member in outcrop, some considered the lower member and the Cohansey Formation to be transitional (Isphording, 1970). Obviously this is not the case as there are three other members (Shiloh Marl, Wildwood, and Belleplain) lying between the lower member and the Cohansey. The age of the lower member was determined from planktic foraminifera and diatoms, and from strontium-isotope age estimates. The foraminiferal assemblage includes Globigerina praebulloides, Globigerinoides trilobus, G. altiapertura, and Globorotalia siakensis. These species are characteristic of the lower Miocene Zone 5 of Blow (1969) of Burdigalian age. The diatom assemblage is characterized by Actinoptychus heliopelta, Aulacodiscus rogersii, Coscinodiscus lewisianus, Sceptroneis caduceus, and Triceratium acutum. These diatoms are characteristic of ECDZ 1 of Andrews (1988), which is considered to be early Miocene (Burdigalian) in age. The strontium-isotope analyses of shells from this member indicate ages from 23 to 20.2 Ma (Aquitanian), thereby extending the age of this member (Sugarman and others, 1993). The pollen in the clay facies of the Kirkwood, as determined from the ACGS-4 drillhole, are oak, hickory, and pine with smaller amounts of beech, black gum, sweet gum, alder, elm, linden, and birch. The sandy facies has essentially the same assemblage but has unusually high concentrations of beech. Exotic species such as Podocarpus and Momipites are common in the unit. The cool floral elements found in the overlying Belleplain and Wildwood Members were not found in the lower member.
Magothy Formation (Upper Cretaceous, middle and lower Santonian)
Magothy Formation - Sand, quartz, fine- to coarse-grained, locally gravelly (especially at the base), white; weathers yellow brown or orange brown, interbedded with thin-bedded clay or dark-gray clay-silt mainly at the top of the formation. Muscovite and feldspar are minor sand constituents. Large wood fragments occur in many clay layers. Clay weathers to gray brown or white. Formation characterized by local vertical and lateral facies changes. The Magothy is best exposed and thickest (about 80 m (262 ft)) in the Raritan Bay area. The outcrop belt is widest in the north and narrows to the southwest. The formation is about 25 m (82 ft) thick or less in the southern sheet. The formation is poorly exposed because of its sandy nature and its widespread cover by younger sediments. The old geologic map of New Jersey (Lewis and Kummel, 1910-1912, revised 1950) showed the Magothy to consist of only one lithology (Cliffwood beds at Cliffwood Beach, Monmouth County). Subsequent pollen studies of the Magothy and the underlying Raritan Formation showed most of the Raritan to be the same age as the Magothy. Wolfe and Pakiser (1971) redefined and considerably expanded the Magothy. Kummel and Knapp (1904) had already recognized that the Magothy, as used here, contained a large number of lithologies. At the time of their study, the Magothy was extensively mined for clay and sand and was well exposed. Their subdivisions had economic designations (for example, Amboy stoneware clay). Barksdale and others (1943) later gave geographic names to these subdivisions, discussed individually below. The lower contact of the Magothy in the Delaware River valley is difficult to place because the lower part of the Magothy is lithically similar to the underlying Potomac Formation. The contact is placed at the base of the lowest dark-gray clay in the Magothy. The best faunas from the Magothy were obtained from siderite concretions and slabs in and near Cliffwood Beach representing only the top of the formation. These faunas were discussed in detail by Weller (1904, 1907) and supplemented by Sohl (in Owens and others, 1977). The presence of Ostrea cretacea in the Cliffwood Beach fauna suggests that the upper part of the Magothy is late Santonian in age. Wolfe and Pakiser (1971) and Christopher (1979, 1982) discussed the microfloral assemblage in the Magothy. Christopher subdivided the Magothy into three zones: Complexipollis exigua-Santalacites minor (oldest), ?Pseudoplicapollis longiannulata-Plicapollis incisa (middle), and ?Pseudoplicapollis cuneata-Semioculopollis verrucosa (youngest). The oldest zone, originally considered to be as old as Turonian, was subsequently considered to be post-Coniacian Christopher, 1982). The middle and upper zones are also probably Santonian. Christopher (1979) followed the nomenclature for the subdivisions elaborated upon earlier. The Cliffwood and Morgan beds, and, presumably the upper thin-bedded sequence, would include the youngest pollen zone; the Amboy Stoneware Clay Member and perhaps the uppermost part of the Old Bridge Sand Member, the middle pollen zone; and the lower part of the Old Bridge Sand Member and South Amboy Fire Clay Member, the oldest pollen zone. The Magothy is considered herein to be of Santonian age. Cliffwood beds - Typically very sandy, horizontally bedded to crossbedded, mainly small-scale trough crossbeds. Thin layers of dark, fine, carbonaceous matter are interbedded with sand. Carbonaceous units are conspicuously micaceous; the sand is less so. Sand is typically fine to medium grained and locally burrowed. Burrows include the small-diameter Ophiomorpha nodosa and some that are not clay lined. Slabs of dark-reddish-brown siderite were common at the base of the bluff at Cliffwood Beach before the outcrop was covered. Some of these slabs had many fossil molds, typically a large number of pelecypods. Lower in the section, between high and low tide level, there is a pale-gray clay-silt about 1.5 m (5 ft) thick with many small reddish-brown siderite concretions. These concretions have many fossils that were described in detail by Weller (1904). The Cliffwood beds are about 7.5 m (25 ft) thick in outcrop. Equivalents of the Cliffwood beds are exposed near the Delaware River between Trenton and Florence, Burlington County. These beds are mainly sand, as are those at Cliffwood Beach, but they tend to have more crossbedding than the typical Cliffwood strata and no burrows or marine fossils. In addition, beds of quartz gravel are present in the Cliffwood near Riverside, Burlington County. Morgan beds - Occur only in the northern part of the central sheet. They consist of interbedded, thin, dark-colored clay and fine-grained, light-colored, micaceous sand. Clay is locally more abundant in the Morgan than in the Cliffwood beds. Sand ranges from massive to locally crossbedded and locally has fine organic matter. This unit is exposed only in the South Amboy quadrangle where it is as much as 12 m (39 ft) thick. It grades downward into underlying clay. Amboy Stoneware Clay Member - Crops out only in the South Amboy quadrangle in the central sheet and is mainly dark-gray, white-weathering, interbedded clay and silt to fine-grained quartz sand. Clay has abundant, fine, carbonaceous matter and fine mica flakes. Small cylindrical burrows are abundant in this unit. Locally, the clay is interbedded with sand and contains large pieces of lignitized, bored (Teredolites) logs. Large slabs of pyrite-cemented sand are associated with the woody beds. Amber occurs in some of the wood. Unit is approximately 7.5 m (25 ft) thick, but pinches out along strike. The Amboy Stoneware is disconformable on the underlying sand. Old Bridge Sand Member - Predominantly a light-colored sand, extensively crossbedded and locally interbedded with dark-gray laminae; clay is highly carbonaceous, woody, in discontinuous beds, especially near the base. The scale of crossbedding varies from small to large. Locally, small burrows are present. Unit is as much as 12 m (39 ft) thick and rests disconformably on the underlying unit. South Amboy Fire Clay Member - Basal member of the Magothy Formation. Unit resembles the Amboy Stoneware Clay Member, particularly in its lensing character. Unit is best exposed in the central sheet in the South Amboy quadrangle and in the Delaware River valley at the base of the bluffs at Florence. The South Amboy is a dark, massive to finely laminated clay, locally oxidized to white or red. Unit fills large channels and has local concentrations of large, pyrite-encrusted, lignitized logs. Some of the clay is slumped, suggesting post-depositional undercutting during channel migration. The clay is interbedded with fine- to medium-grained, crossbedded sand. The basal contact with the underlying Raritan is well exposed in the Sayre and Fisher Pit in Sayreville, Middlesex County, where the contact is marked by a deeply weathered gravel zone.
Manasquan Formation (lower Eocene, Ypresian)
Manasquan Formation - Consists of several lithologies. In the northern part of the central sheet, unit consists of a lower, clayey, quartz-glauconite sand, which is exposed intermittently along the Manasquan River near Farmingdale, Monmouth County, and an upper, finegrained quartz sand or silt, which is exposed along Hog Swamp Brook west of Deal, Monmouth County. The Farmingdale Member and the Deal Member (of Enright, 1969) are not used on this map because they are not continuous through the outcrop belt or in the subsurface. The formation is best exposed in the central sheet from the Fort Dix Military Reservation, Burlington County, southwestward to the Medford Lakes quadrangle. Here the lower part of the formation consists of 5 m (16 ft) of medium- to coarse-grained, massive, dark-grayish-green, glauconite-quartz sand. The lowest 1 m (3 ft) mostly contains calcareous debris and phosphatized internal fossil molds reworked from the underlying Vincentown Formation. The upper part of the formation is approximately 8 m (26 ft) thick and is mostly a very clayey, blue-green to pale-gray, quartz-glauconite (about 20 percent glauconite) sand. Locally, the glauconite content of this interval is variable, and the unit becomes almost a bluegreen clay-silt, especially near Pemberton, Burlington County (Owens and Minard, 1964a). Casts and molds of mollusks (especially Venericardia perantiqua) occur in outcrop. The age of the formation was determined from microfauna in unweathered subsurface beds. Calcareous nannofossils indicates upper Zone NP 9 to mid Zone NP 14 (early Eocene).
Manasquan Formation (lower Eocene, Ypresian)
Manasquan Formation - Clay to clay-silt, massive to finely laminated, green to gray-green, extensively bioturbated. Calcareous microfossils are abundant in this unit. In the northwestern outcrop belt and shallow subsurface of the central sheet, the lower beds of the Manasquan Formation consist of a maximum of 10 m (33 ft) of fine- to coarse-grained, somewhat clayey, bluish-green glauconitic quartz sand. No calcareous macrofossils were found in this lithology. The sand minerals in the basal sand facies, excluding glauconite, consist of quartz, feldspar (10 to 25 percent), and siliceous rock fragments (a few percent). The glauconitic quartz sand is overlain to the southwest by a light- to dark-green, locally glauconitic, sandy clay-silt. This clay-silt is present at the base of the unit in the shallow subsurface. Eastward and in the intermediate subsurface, the Manasquan is primarily a clayey glauconite sand. In the deep subsurface, the Manasquan is primarily a massive to finely laminated, lightyellow clay-silt that has high concentrations of calcareous microfossils and has several hard indurated layers. In general, the formation thickens to the southeast where it is more than 60 m (197 ft) thick. The basal contact with the underlying Vincentown Formation is sharp and contains a thin zone, typically 0.61 m (2 ft) thick, of reworked glauconite sand, phosphatic debris, and sparse quartz granules. Gamma-ray logs through the Manasquan Formation have a large gamma spike along the basal contact. The age of the Manasquan was determined from calcareous nannofossils and, to a lesser degree, from foraminifera. The lower part of the Manasquan is assigned to the upper part of Zone NP 9 on the basis of the calcareous nannofossils Campylosphaera dela and Lophodolithus nascens and the absence of Zone NP 10 species. The upper part of the formation lies within Zone NP 13. This zone is characterized by the absence of Rhomboaster orthostylus and the presence of Discoaster lodoensis (Poore and Bybell, 1988). The foraminifera Planorotalites palmerae, which is present in this unit, has a range that correlates with the lower part of Zone NP 13 (Poore and Bybell, 1988).
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.
Marshalltown Formation (Upper Cretaceous, upper and middle Campanian)
Marshalltown Formation - Sand, quartz and glauconite, fine- to medium-grained, silty and clayey, massive, dark-gray; weathers light brown or pale red, extensively bioturbated. Very glauconitic in basal few meters; glauconite concentration decreases upward so that in upper part of unit, quartz and glauconite are nearly equal. Feldspar, mica, pyrite, and phosphatic fragments are minor sand constituents. Locally, very micaceous (mostly green chlorite) with sparse carbonized wood fragments. Fine-grained pyrite abundant throughout formation. Local thin, pebbly zones with large fossil impressions occur in the middle of the formation. In the upper part of the formation, quartz increases to about 40 percent. Unit crops out in a narrow belt throughout the map area and forms isolated outliers in the central sheet. Best exposures are along Crosswicks Creek in the Allentown quadrangle. In the southern sheet, the Marshalltown underlies a narrow belt in the uplands and broadens to the southwest. Many Marshalltown exposures occur along Oldmans Creek and its tributaries near Auburn, Gloucester County. The contact with the underlying Englishtown Formation is sharp and unconformable. The basal few centimeters of the Marshalltown contain siderite concentrations, clay balls, and wood fragments reworked from the underlying Englishtown. Many burrows, some filled with glauconite, project downward into the Englishtown for about one meter (3 ft) giving a spotted appearance to the upper part of the Englishtown (Owens and others, 1970). The Marshalltown is the basal transgressive unit of a sedimentation cycle that includes the regressive deposits of the overlying Wenonah and Mount Laurel Formations resembling the overlying Red Bank Formation to Navesink Formation cycle in its asymmetry. Within the map area, only a few long-ranging megafossils occur in the Moorestown quadrangle (Richards, 1967). To the south, in the type area, Weller (1907) reported diverse molluskan assemblages indicating a Campanian age. More importantly, Olsson (1964) reported the late Campanian foraminifera Globotruncana calcarata Cushman from the upper part of the formation. No G. calcarata were found during our investigations. Wolfe (1976) assigned the pollen assemblage of the Marshalltown to the CA5A Zone considered to be Campanian. The Marshalltown has most recently been assigned to Zone CC 20-21 (Sugarman and others, 1995) of middle and late Campanian age (Perch-Nielsen, 1985).
Merchantville Formation (Upper Cretaceous, lower Campanian)
Merchantville Formation - Sand, glauconite, locally has high quartz content, very clayey and silty, massive to thick-bedded, grayish-olive-green to dark-greenish-gray; weathers moderate brown or moderate yellow brown. Mica, feldspar, and pyrite are minor sand constituents. Very micaceous at base. Locally, has extensive iron incrustations in near-surface weathered beds. Fossil molds are mostly phosphatic. Fossils typically occur in siderite concretions. No calcareous fossils were found in outcrop. The Merchantville forms a continuous narrow to wide belt throughout the map area. The unit is about 6 m (20 ft) thick in the northern part of the central sheet, about 20 m (66 ft) thick in the Trenton area, and 12 to 15 m (39-49 ft) thick throughout the southern sheet. The formation is best exposed in the Trenton East quadrangle, mainly in the tributaries on the western side of Blacks Creek and south of Bordentown, Burlington County, where the entire thickness of the formation can be seen in gullies (Owens and Minard, 1964b). The basal contact with the underlying Magothy or Cheesequake Formations is sharp and disconformable. At most places, a reworked zone about 0.3 to 1 m (1-3 ft) thick is present at the base. This basal bed contains reworked lignitized wood, siderite concretions as much as 13 cm (5 in) in diameter, scattered pebbles and coarse-grained quartz sand and is burrowed. Most burrows project downward into the underlying formations. The Merchantville is the basal bed of a lower Campanian transgressive-regressive cycle that includes the overlying Woodbury and Englishtown Formations. Merchantville faunas were analyzed by Sohl (in Owens and others, 1977) who concluded that northern fauna represented deposition on a lower shoreface or in the transition to an inner shelf, whereas the southern fauna was a deeper water assemblage, probably inner shelf. Macrofossils occur as internal and external molds and include the ammonites Menabites (Delawarella) delawarensis and Scaphites (Scaphites) hippocrepis III. The Scaphites is of the type III variety of Cobban (1969) and is indicative of the lower, but not the lowest, Campanian. More recently, Kennedy and Cobban (1993), detailing the ammonite assemblage that includes Baculites haresi, Chesapeakella nodatum, Cryptotexanites paedomorphicus sp., Glyptoxoceras sp., Menabites (Delawarella) delawarensis, M. (Delawarella) vanuxemi, Menabites (Bererella) sp., Pachydiscus (Pachydiscus) sp., Placenticeras placenta, Pseudoscholenbachia cf. P. chispaensis, Scaphites (Scaphites) hippocrepis III, Submortoniceras punctatum, S. uddeni, and Texanites (Texanites) sp., concluded that the Merchantville is of late early Campanian age. Wolfe (1976) indicated that the Merchantville microflora was distinct from overlying and underlying units and designated it Zone CA2 of early Campanian age.
Navesink Formation (Upper Cretaceous, Maastrichtian)
Navesink Formation - Sand, glauconite, medium-grained, clayey and silty, massive, dark-gray to dark-gray-green, extensively bioturbated, locally contains large calcareous shells; sand-size mica, locally abundant; weathers light brown or red brown. Basal quartz sand is fine- to coarse-grained, pebbly, massive, light-yellow, and somewhat glauconitic, as much as 2 m (7 ft) thick and formed by the reworking of the underlying Mount Laurel Formation (Owens and others, 1977). Exogyra costata and the belemnite Belemnitella americana occur in the basal quartz sand. Crops out in a narrow belt throughout map area. Fresh exposures occur along tributaries of Raccoon Creek near Mullica Hill, Gloucester County. The Navesink is 3 to 7.5 m (10-25 ft) thick. The Navesink and Red Bank deposits represent a transgressive (Navesink)-regressive (Red Bank) cycle of sedimentation (Owens and Sohl, 1969). The cycle is unconformity-bounded at top and bottom. Within the cycle, the formational contact is gradational. The age of the Navesink was determined from both the macrofauna and microfauna. Planktic foraminifera from the lower part of the Navesink are indicative of the Rugotruncana subcircumnodifera Subzone of early Maastrichtian age (Smith, in Owens and others, 1977). The upper part contains the mollusks Exogyra costata, Sphenodiscus lobatus, and Pycnodonte vesicularis indicating a middle to late Maastrichtian age. Planktic foraminifera from the upper part represent the Gansserina gansseri Subzone of middle Maastrichtian age (Smith, in Owens and others, 1977). Pollen in the Navesink and Sandy Hook Member of the Red Bank are similar; the Navesink microflora is a CA6/MA-1 Zone in Wolfe's (1976) classification. The Navesink, therefore, ranges from early to late Maastrichtian. Sugarman and others (1995) assigned a middle Maastrichtian Zone CC 25 to the Navesink.
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 Conglomerate and Sandstone facies (Lower Jurassic and Upper Triassic)
Passaic Formation Conglomerate and Sandstone facies - 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).
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.
Potomac Formation (Upper Cretaceous, lower Cenomanian)
Potomac Formation - Predominantly clay to clay-silt, thinly laminated to thick-bedded, mottled red, white, and orange-brown, less commonly dark-gray and woody; interbedded with thin beds and lenses of very fine to medium-grained, massive, white to orange-brown, micaceous sand. Lithologies are typical of the shallow subsurface. Down dip, these lithologies interfinger with thin to thick beds of marine clay-silt, commonly glauconitic and locally shelly. Marine beds are most prevalent in the southernmost part of the southern sheet. Unit 3 was cored in its entirety at Freehold where it is approximately 75 m (246 ft) thick. In the core, the basal 6 m (20 ft) consists of red or mottled red and white clay interbedded with gravel and fine- to coarse-grained sand. The clay is pervaded by reddish-brown siderite. Most of the overlying beds consist of interbedded dark-colored clay, locally weathered to pale yellow or white, and fine- to medium-grained, light-colored sand. Layers that contain fine black carbonaceous material to large lignitized wood pieces are common in unit 3 in this core. At Toms River, the unit is about 60 m (197 ft) thick and consists of dark- to pale-gray clay, locally weathering to white or yellowish gray, and light-colored, micaceous sand. In general, the darker colored clay is more common in the upper part of the section. Locally, the sand has very small amounts of glauconite which may indicate some local marine influence during sedimentation. The age of unit 3 was determined from pollen in the nonmarine deposits and foraminifera in the marine sections. Typical forms found in Zone III in New Jersey are Ajatipollis sp. A, Tricolpites nemejci, T. vulgaris, Tricolporoidites bohemicus, Tricolporoidites sp. A, T. sp. B, and Tricolporopollenites sp. B (Doyle and Robbins, 1977). In the marine facies, Petters (1976) reports a planktic foraminiferal suite containing Praeglobotruncana delrioensis and Rotalipora greenhornensis. Both the pollen and foraminiferal assemblages suggest an early Cenomanian age.
Raritan Formation (Upper Cretaceous)
Raritan Formation (Cook, 1868) - Consists of upper clayey-silt (Woodbridge Clay Member) and lower sand (Farrington Sand Member) in map area. Woodbridge Clay Member is palered-orange weathering, grayish-black to dark-gray micaceous silt, very clayey; interbedded and locally interbedded with light-gray, very clayey, fine- to very-fine-grained micaceous sand containing primarily quartz and feldspar. Abundant layers of small, pyrite-coated wood fragments. Siderite in discontinuous beds and in flattened slab concretions as much as 1 m (3 ft) in diameter are common. Mollusk casts common in siderite near top of formation. Typically about 24 m (80 ft) thick. Farrington Sand Member is white, fine-to medium-grained, very micaceous, crossbedded sand, interbedded with thin to thick, darkgray, silty beds. Exposed only in pits dug below the overlying Woodbridge Clay Member. Typically about 8 m (25 ft) thick. Fossils include late Cenomanian ammonites Metoicoceras bergquisti and Metengonoceras sp. in upper part of Woodbridge (Cobban and Kennedy, 1990) and pollen of the Complexipollis-Atlantopollis assemblage zone (= Zone IV) of late Cenomanian to early Turonian age (Christopher, 1979; 1982).
Raritan Formation (Upper Cretaceous, upper Cenomanian)
Raritan Formation - Clay, silty, massive, dark-gray, shelly. Unit is generally restricted to the deep subsurface and only subcrops in the northern part of the central sheet. Petters (1976) proposed a new formation, the Bass River Formation, which included the Raritan as well as the lowermost part of the Magothy and the uppermost part of the Potomac Formation, unit 3. In this report, the name Bass River is not used. Thickness values were obtained from interpretations of geophysical logs from the few drillholes that penetrated this formation; consequently, these values are, at best, speculative. It is estimated that the Raritan is at most 100 m (328 ft) thick in the southernmost part of New Jersey. The formation contains both nonmarine and marine facies. The Freehold drillhole shows the best section containing both facies. In this drillhole the Raritan is approximately 60 m (197 ft) thick. The lower 12 m (39 ft) consists of interbedded, fine- to medium-grained, thin- to thick-bedded, light to dark-colored quartz sand and light- to dark-colored clay or clayey silt. Small to large pieces of lignitized wood are characteristic of and common to abundant in these beds. The middle 30 m (98 ft) consists of laminated to thinly bedded, dark-gray, micaceous clay and fine-grained, light-colored, micaceous quartz sand. Reddish-brown secondary cementation is common in the strata of this interval. Lignitized wood fragments are also locally abundant in these beds but on average the wood pieces are much smaller than those seen in the basal beds. The upper 18 m (59 ft) also is dominated by the laminated to thin-bedded sequences of micaceous clay and quartz sand but has small amounts of glauconite sand. A thin layer of large fossils (primarily Exogyra woolmani) is present in these upper beds. At the very top of this interval some of the beds are cemented by siderite. In general, the Raritan appears to be fluvial in the lower part, marginal marine in the middle, and marine at the top. North and west of the Freehold drillhole the Raritan is mostly interbedded nonmarine crossbedded sand and black to variegated clay. At Island Beach, southwest of Freehold, the Raritan is wholly marine and consists largely of dark-gray, shelly, micaceous clay at the base and fine-grained, dark-gray, shelly, micaceous clay at the top. It is assumed that the Raritan is late Cenomanian to possibly early Turonian in age as determined from northern New Jersey sections. In outcrop, the Raritan is early late Cenomanian in age on the basis of ammonites (Cobban and Kennedy, 1990). Pollen from these outcrops belongs to the Complexiopollis-Atlantopollis Assemblage Zone (zone IV, Christopher, 1979). Downdip, Petters (1976) reports the planktic foraminifer Marginotruncana helvetica, a middle Turonian marker, from beds assigned to pollen zone IV at Toms River, Ocean County.
Raritan Formation (Upper Cretaceous, upper Cenomanian)
Raritan Formation - Consists of an upper clayey silt (Woodbridge Clay Member) and a lower sand (Farrington Sand Member). Formation occurs only in northern part of central sheet. Woodbridge Clay Member - Silt, clayey, dark-gray; weathers to red brown or white, locally interbedded with light-gray, clayey, fine- to very fine grained sand (primarily quartz and mica with little feldspar). Very micaceous (muscovite, chlorite, and biotite) in both silty and sandy beds. Very woody, mostly fine pieces in layers and coated with pyrite. Locally, tree stumps, in upright position, are found near base of unit as are transported individual logs several feet in length. Siderite occurs in discontinuous beds and as flattened slab concretions as much as 0.6 m (2 ft) in maximum diameter. Fossil casts of marine mollusks are present, particularly near the top of the formation. Locally, well-developed burrows of Ophiomorpha nodosa filled with iron oxides weather out of the clay-silt. The Woodbridge is approximately 20 m (66 ft) thick in the vicinity of Sayreville, Middlesex County, where the South River has stripped away the overlying Magothy Formation, and it crops out in many places in the Perth Amboy and New Brunswick quadrangles to the north, but not in the quadrangles to the south or southwest. The Woodbridge does not crop out in the Delaware River valley southwest of Trenton. The late Cenomanian ammonites Metoicoceras bergquisti and Metengonoceras sp. were described from the upper part of the Woodbridge (Cobban and Kennedy, 1990). Pollen from the unit belongs to the Complexipollis-Atlantopollis Assemblage Zone of latest Cenomanian and early Turonian age (Christopher, 1979, 1982). Farrington Sand Member - Sand, quartz, fine- to medium-grained, crossbedded, very micaceous, white, interbedded with thin to thick, dark, silt beds. Rock fragments are a minor sand constituent. No burrows were observed in the unit. Unit is exposed only in pits dug below the overlying Woodbridge Clay Member. Typically, thickness is about 9 to 10.5 m (30-34 ft). Pollen from the Farrington is similar to the pollen in the Woodbridge.
Rondout and Decker Formations, undivided (Lower Devonian and Upper Silurian)
Rondout and Decker Formations, undivided - Rondout Formation (Clarke and Schuchert, 1899) - Upper part is medium-gray weathering, medium-dark-gray, very fine to fine-grained, medium-bedded, fossiliferous, argillaceous limestone. Middle part is light-medium-gray-weathering, medium-gray, laminated to medium-bedded, argillaceous dolomite. Locally contains deep desiccation polygons. Lower part is medium-gray-weathering, medium- to dark-gray, very fine to medium-grained, medium-bedded fossiliferous limestone. Silurian-Devonian boundary placed in middle of formation (Denkler and Harris, 1988). Lower contact abrupt and placed at top of highest calcareous quartz sandstone. Thickness approximately 12 m (40 ft). Decker Formation (White, 1882) - Light-gray- to yellowish-gray-weathering, light- to medium-gray, calcareous quartz siltstone, sandstone, and fine-pebble conglomerate locally interbedded with fossiliferous medium-gray, medium- to coarse-grained limestone and very fine grained, thin- to medium-bedded dolomite. Lower contact gradational. Thickness varies from 15 m (50 ft) near Duttonville to 25 m (82 ft) at Wallpack Center.
Shark River Formation (upper and middle Eocene, Priabonian through Lutetian)
Shark River Formation - Consists of three lithofacies, a basal clayey, greenish-gray glauconite sand; a middle dark-green to gray-green silty clay or clayey silt; and an upper medium-gray to gray-green, silty quartz sand. Updip beds are cyclic with a fine- to medium-grained, somewhat clayey, fossiliferous, dark-green, glauconite-quartz (25 percent) sand at the base. The basal lithofacies is about 12 m (39 ft) thick in the southern sheet and 3 m (10 ft) thick in the central sheet. There is a general increase in quartz sand upward and a change in color to dark gray or brownish gray. Locally, some of the beds are more clayey and have more calcareous shell fragments. The middle clay and silt facies is typically the thickest lithofacies in most Shark River sections (as much as 38 m (125 ft) thick) and is massive to thick bedded. The thick-bedded parts typically consist of intercalated silty and clayey beds that are extensively bioturbated. Macro- and microfossils are abundant in this facies. Most of the macrofossils are thin-walled pelecypods. This facies is gradational into the upper quartz-sand facies. The quartz sand is well developed in the Toms River Chemical Plant drillhole, Toms River, Ocean County (sheet 1). This facies apparently was beveled off in the updip areas during erosion prior to deposition of the Kirkwood Formation. The Shark River Formation in the updip area near Bridgeton, Cumberland County (sheet 2), is about 52 m (171 ft) thick. All of the Shark River lithologies in the downdip area are extensively bioturbated. The Shark River is thickest (more than 60 m (197 ft)) in a trough that lies near the middle of the southern sheet. The contact between the Shark River and the underlying Manasquan Formation is sharp and contains a thin zone of reworked glauconite sand, granules of quartz, and phosphatic debris. On most gamma-ray logs through this contact, there is a sharp gamma high reflecting the concentration of phosphatic sediment. The vertical arrangement of facies in this formation is from a transgressive (mostly clay) facies at the base to a regressive (mostly sand) facies at the top. Calcareous nannofossils and foraminifera were used to date this unit. Where the unit is thickest, the nannofossils range from the upper part of Zone NP 14 (Rhabdosphaera inflata) to the lower part of Zone NP 18 (Chiasmolithus oamaruensis). The entire sequence of Zones NP 14 through NP 18 was observed only in the ACGS-4 corehole near Mays Landing. The planktic foraminifera zones range from the Turborotalia frontosa Zone at the base to the Turborotalia pomeroli/Turborotalia cerroazulensis Zone at the top. A middle to early late Eocene age for the Shark River is indicated by these zones (Poore and Bybell, 1988).
Shark River Formation (upper and middle Eocene, Priabonian through Lutetian)
Shark River Formation - Glauconite sand, silt, and clay, medium- to coarse-grained, light-brown to medium-gray, locally indurated at top and noncalcareous throughout. Mollusk impressions (mainly Venericardia perantiqua) were observed in the Farmingdale quadrangle. The Shark River is exposed only at a few localities in the central sheet near Farmingdale, Monmouth County, along the Manasquan and Shark Rivers and in several tributaries to Deal Lake near Asbury Park in the Asbury Park quadrangle (Sugarman and Owens, 1994). Most outcrops are small, less than 3 m (10 ft) in height. The contact with the underlying Manasquan Formation was not observed. The Shark River is about 18 m (59 ft) thick and consists of two fining-upward cycles: a glauconite sand is present at the base and a clay or silt is present at the top of each cycle. Calcareous nannofossils in subsurface Shark River sections indicate Zones NP 14 through NP 18 (Martini, 1971) (middle Eocene and early late Eocene).
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).
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).
Towaco Formation Conglomerate and Sandstone facies (Lower Jurassic)
Towaco Formation Conglomerate and Sandstone facies - Conglomerate and conglomeratic sandstone with subrounded quartzite and quartz clasts in matrix of light-red sand to brownish-red silt (Jtc) interfingers with rocks of the Towaco Formation north and west of New Vernon.
Unnamed Formation at Cape May (upper Pliocene)
Unnamed Formation at Cape May - Interbedded gravel, sand, and clay, massive to thickbedded. Informal unit described from a corehole at the Cape May Airport. The lower 18.3 m (60 ft) consists of interbedded gravel; medium- to very coarse grained, poorly sorted sand; and thin to thick beds of medium- to dark-gray, very woody clay. Gravel clasts are typically less than 0.64 mm (0.025 in) in diameter. The upper 12.2 m (40 ft) consists of a thick-bedded, medium-gray, extensively bioturbated clay-silt, which is overlain by an extensively burrowed, fine- to medium-grained glauconitic (about 5 percent) quartz sand. Quartz and siliceous rock fragments compose most sand grains. Feldspar is present in most samples but usually constitutes less than 10 percent of the sand fraction. No calcareous macrofossils were found in the burrowed intervals. Unit is known only to occur on the Cape May peninsula where it lies within a large channel. The unit is about 60 m (197 ft) in maximum thickness. The contact with the underlying Belleplain Member of the Kirkwood Formation is sharp and unconformable; a basal gravel bed as much as 1 m (3 ft) thick is present along the contact. The pollen assemblage in the lower part of the unit is dominated by pine and oak with somewhat lesser amounts of hickory and basswood. Spruce, hemlock, beech, alder, and black gum are minor constituents. Traces of fir, willow, birch, and sweet gum are present, as is exotic Engelhardia. The nonarborial pollen are a Multisia-type composite of the present-day Andean provenance which indicate an exotic cool climate. The lower assemblage suggests a cool-temperate climatic regimen. The pollen assemblage in the upper beds is dominated by oak and hickory with minor amounts of basswood, sweet gum, pine, and Multisia-type composite. Traces of cedar, willow, birch, alder, grass, and Sphagnum spores also are present. This assemblage probably represents a temperate climatic regimen (Les Sirkin, Adelphi University, written commun., 1991). The low percentage of exotic species is characteristic of the late Pliocene, and therefore, the unnamed unit at Cape May may be equivalent to the Beaverdam Formation of the Delmarva Peninsula of Delaware, Maryland, and Virginia.
Vincentown Formation (upper Paleocene, Selandian)
Vincentown Formation - Upper part, sand, glauconite (35-40 percent) and quartz (60-65 percent), fine- to very fine grained, very clayey and silty, massive, dark-gray, bioturbated, very micaceous. Lower part, sand, massive, less micaceous and clayey, dark-gray-green. The lower 4.5 m (15 ft) of the formation is a fine- to medium-grained, clayey glauconite sand. Locally, there is an accumulation of disarticulated calcareous shells along the contact with the underlying Hornerstown Formation. These shells are commonly the brachiopod Oleneothyris harlani or the mollusk Gryphaea dissimilaris. Where the shell bed is absent it is difficult to separate glauconite sand of the basal part of the Vincentown from the underlying Hornerstown Formation, which also is a glauconite sand. Gamma logs through this interval show that there is a small gamma spike along the contact between the glauconite sands. The grain size decreases and the formation is significantly more clayey downdip. At Allaire State Park, Monmouth County (drillhole Allaire-C), for example, the bulk of the Vincentown is a clayey, very micaceous, dark-gray, slightly feldspathic quartz sand. Large fossils, which are abundant in the near-surface beds, are absent. In addition, the basal glauconite beds tend to thicken somewhat downdip. Farther basinward, the bulk of the formation is an unfossiliferous, gray-green to locally tan clayey silt or silty clay. Locally, a thin- to thick-bedded glauconite sand occurs at the base. In the thickest downdip section penetrated at Island Beach, the Vincentown is mostly a pale-gray to dark-gray clay-silt. No megafossils were observed in the Island Beach core. On the basis of geophysical log interpretations in the deepest subsurface, this unit has a maximum thickness of about 38 m (125 ft). The age of the Vincentown is best indicated by calcareous nannofossils, which indicate Zones NP 5 to NP 9 (Bybell, 1992). Common nannofossils from Zone NP 5 are Chiasmolithus bidens, Ellipsolithus distichus, Fasciculithus tympaniformis, Scapholithus fossilis, and Toweius eminens. Common nannofossils in Zone NP 9 are Biantholithus astralis, Chiasmolithus bidens, Discoaster multiradiatus, D. salisburgensis, Fasciculithus involutus, F. schaubii, F. thomasii, and Lophodolithus nascens. The upper part of the Vincentown falls within the upper part of Zone NP 9 and therefore is late Paleocene (Selandian) in age.
Vincentown Formation (upper Paleocene, Selandian)
Vincentown Formation - Sand, quartz, medium-grained, well- to poorly sorted, dusky-yellow to pale-gray; weathers orange brown or red brown, typically very glauconitic and clayey near base; glauconite decreases up section. Feldspar and mica are minor sand constituents. Unit best exposed in the Pemberton, New Egypt, and Mount Holly quadrangles of the central sheet where the overlying formations have been stripped away. The Vincentown Formation is as much as 30 m (98 ft) thick and averages 3 to 15 m (10-49 ft) in its subcrop belt. Where unweathered the unit is generally a shelly sand; where weathered the unit is largely a massive quartz sand. The unweathered sand of the Vincentown is exposed intermittently along the Manasquan River near Farmingdale, Monmouth County. The calcareous nature of the unweathered Vincentown was observed in several coreholes in the vicinity of Farmingdale. The contact with the underlying Hornerstown Formation is disconformable; locally shell beds (bioherms) up to 1.5 m (5 ft) thick are found along the contact. Shells in the bioherms are typical of a restricted environment and contain the brachiopod Oleneothyris harlani (Morton) in the lower beds and the oyster Pycnodonte dissimilaris in the upper beds. The basal contact and the Oleneothyris bioherms are exposed along Crosswicks and Lahaway Creeks and their tributaries. Where bioherms are absent, the basal contact is difficult to place within a sequence of glauconite beds. In general, glauconite beds of the Vincentown are darker gray than glauconite beds of the Hornerstown, and the Vincentown has more quartz sand. Upper beds of the Vincentown are as much as 12 m (39 ft) thick and are mostly silty, darkgray to green-gray, massive, glauconite sand that contains a small percentage of quartz. Calcarenite or coquina, characterized by an abundance of bryozoans, occurs locally along the western belt. These fossiliferous beds, 6 to 7.5 m (20-25 ft) thick, are best exposed along Shingle Run in the New Egypt quadrangle area and in streams that cross the Vincentown outcrop belt in the Pemberton quadrangle. Calcareous nannofossils, present in some Vincentown outcrops, are from Zones NP 5 (the Oleneothyris beds) and NP 9 (late Paleocene). Vincentown sediments are much more fossiliferous in the subsurface and contain Zones NP 5 through NP 9, inclusive. Therefore, the Vincentown corresponds in age with the Aquia Formation of Virginia and Maryland. Numerous studies of the foraminifera of the Vincentown from calcareous beds in the western outcrop belt indicate that the Vincentown includes the planktic foraminifera Zones P3b through P6a (Olsson and others, 1988). A potassium-argon age of 56.4 +/- 18 Ma was determined for basal beds near New Egypt, Ocean County (Owens and Sohl, 1973).
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).
Wenonah Formation (Upper Cretaceous, upper Campanian)
Wenonah Formation - Sand, quartz and mica, fine-grained, silty and clayey, massive to thick-bedded, dark-gray to medium-gray; weathers light brown to white, extensively bioturbated, very micaceous, locally contains high concentrations of sand-sized lignitized wood and has large burrows of Ophiomorpha nodosa. Feldspar (5-10 percent) is a minor sand constituent. Unit crops out in a narrow belt from Sandy Hook Bay on the central sheet and pinches out southwest of Oldmans Creek, Salem County, on the southern sheet. Isolated outliers of the Wenonah are detached from the main belt in the central sheet area. Thickness is about 10 m (33 ft) in the northern part of the central sheet, 20 m (66 ft) in the southwestern part of the central sheet, and 7.5 m (25 ft) in the southern sheet. The Wenonah is gradational into the underlying Marshalltown Formation. A transition zone of several meters is marked by a decrease in mica and an increase in glauconite sand into the Marshalltown. Fossil casts are abundant in the Wenonah. Weller (1907) reported Flemingostrea subpatulata Hop Brook in the Marlboro quadrangle indicating a late Campanian age. Wolfe (1976) placed the Wenonah microflora in his CA5A assemblage, considered to be of late Campanian age. Kennedy and Cobban (1994) identified ammonites including Baculites cf. B. scotti, Didymoceras n. sp., Menuites portlocki, Nostoceras (Nostoceras) puzosiforme n. sp., Nostoceras (Nostoceras) aff. N. colubriformus, Parasolenoceras sp., Placenticeras placenta, P. minor n. sp., and Trachyscaphites pulcherrimus. The presence of M. portlocki and T. pulcherrimus indicates late, but not latest, Campanian.
Wildwood Member of the Kirkwood Formation (middle and lower Miocene, Langhian and Burdigalian)
Wildwood Member - New member named for a well drilled at Wildwood, Cape May County. Typically consists of a very fossiliferous, micaceous, darkgray clay-silt interbedded with fine- to medium-grained, pale-gray-brown sand in lower half of the member. The upper half of the member is more sandy (mostly fine-grained, micaceous quartz sand), thin-bedded to laminated, commonly interbedded with thin-bedded, gray-brown, micaceous clay; wood fragments are common. The basal contact with the underlying unit is sharp and has considerable relief. A 1-m (3-ft)-thick bed of gravel (1 cm (0.4 in) in maximum diameter) with pieces of quartz and worn shells, commonly occurs along the contact. Thickness of the unit varies widely because of the undulating basal contact. The maximum thickness, 80 m (262 ft), was penetrated in the Wildwood well. At the Island Beach well (290019) at Island Beach State Park, Ocean County, the Wildwood is over 30 m (98 ft) thick. The lower 6 m (20 ft) consists of thick interbeds of fine- to medium-grained, massive to locally thick-bedded, extensively bioturbated, micaceous quartz sand and dark-brown and grayish-brown silty clay. The middle part is mostly massive to finely laminated, dark-gray to gray-brown silt to clay. The upper 6 m (20 ft) consists of fine- to coarse-grained, locally gravelly, thin- to thick-bedded sand interbedded with the clay and silt. The age of the Wildwood was determined from diatoms and strontium-isotope age estimates of mollusk shells. The diatom assemblages in this unit fall within Andrews (1988) ECDZ 2, thus indicating a considerable unconformity between this member and the overlying Belleplain (ECDZ 6). ECDZ 2 is in the Delphineis ovata Zone and contains the characteristic diatoms Coscinodiscus lewisianus, Delphineis lineata, Rhaphidodiscus marylandicus, Rhaphoneis fusiformis, R. margaritata, R. wicomicoensis, Sceptroneis caduceus, S. grandis, and S. hungarica. Strontium-isotope analyses on shells from this interval indicate an age range of 17.4 to 15.5 Ma (Sugarman and others, 1993). The isotopic and paleontologic ages suggest that the Wildwood Member straddles the early-middle Miocene boundary (Langhian-Burdigalian boundary). Pollen from the Wildwood has warm-temperate affinities in the lower part and mixed warm- and cool-temperate affinities in the upper part suggesting an overall cooling of the climate during the time of deposition. Collectively, the Wildwood and Belleplain Members constitute the section that Woolman (1889-1902) assigned to his "great diatom bed".
Wildwood Member of the Kirkwood Formation (middle and lower Miocene, Langhian and Burdigalian)
Wildwood Member - Clay, silty, massive to finely bedded, dark-gray to olive-gray, locally interbedded with thin beds of light-colored sand. Contains small shell fragments primarily at base. Upper beds are more sandy than lower beds but also contain many thin to thick beds of clay. The sand is fine to medium grained, light gray, and commonly has dispersed wood fragments. Shell fragments are locally present in this facies. Basal beds are micaceous, locally diatomaceous, and contain wood fragments. Quartz is the major sand constituent with minor amounts of siliceous rock fragments and feldspar. The Wildwood subcrops beneath surficial deposits where the Belleplain Member and Cohansey Formation were stripped away. Along Delaware Bay, the Wildwood subcrops from near the Cohansey River to Fortescue, Cumberland County. Along the Atlantic Coast, the unit subcrops from Bay Shore Park to near Beach Haven Park, Ocean County. The maximum thickness of the unit is about 18 m (59 ft). The contact with the underlying Shiloh Marl Member is sharp and unconformable. Diatoms from the Wildwood Member are from the East Coast Diatom Zone (ECDZ) 2 of Andrews (1988) indicating a latest Burdigalian and Langhian age (late early and early middle Miocene).
Woodbury Formation (Upper Cretaceous, lower Campanian)
Woodbury Formation - Clay-silt, dark-gray; weathers brown and orange pink. Iron oxides fill fractures or form layers in the most weathered beds. Unit is massive except at the base where thin quartz sand layers occur. Locally, thin stringers of pale-greenish-brown, smooth-surface glauconite occur near the top. Unit conspicuously micaceous throughout and contains finely dispersed pyrite, carbonaceous matter, and small pieces of carbonized wood as much as 30 cm (12 in) in length. Small siderite concretions are abundant in the Woodbury in the northern part of the outcrop belt. Unit forms a broad belt in the central sheet from Sandy Hook Bay, southwest to area around East Greenwich, Gloucester County, where it pinches out or changes facies. The Woodbury maintains a thickness of about 15 m (49 ft) throughout most of its outcrop belt. Fossil imprints are abundant. An extensive Woodbury macrofauna was described by Weller (1907) from siderite concretions from a tributary to the Cooper River in the Camden quadrangle. This assemblage is unusual in that it is the only existing outcrop of the Woodbury where calcareous and aragonitic shells are still intact. Most fossils are small, fragmented, and concentrated in small pockets, but larger intact calcareous fossils are scattered throughout the Woodbury. Weller (1907) recorded 57 species from this locality. In addition, this is the same locality that contains fossils of the dinosaur Hadrosaurus foulkii. Pollen collected from the Woodbury was assigned to the CA3 Zone by Wolfe (1976). Biostratigraphic data suggest that the Woodbury is of early Campanian age.
New Mexico
McRae Formation (Phanerozoic | Mesozoic | Cretaceous)
McRae Formation; Engle basin - Cutter sag area; Maastrichtian
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, limestone, meta-andesite, phyllite, and shale (Devonian to Mississippian)
CONGLOMERATE, LIMESTONE, META-ANDESITE, PHYLLITE, AND SHALE-Includes Grossman, Banner, Nelson, and Mountain City Formation. Northern Elko County
Continental deposits of siltstone, shale, conglomerate, and limestone (Cretaceous)
CONTINENTAL DEPOSITS OF SILTSTONE, SHALE, CONGLOMERATE, AND LIMESTONE-Includes units such as King Lear Formation in Humboldt County, Newark Canyon Formation in Eureka County, Willow Tank Formation and baseline Sandstone in Clark County
Continental sedimentary rocks (Late Cretaceous to Eocene)
CONTINENTAL SEDIMENTARY ROCKS-Includes units such as Pansy Lee Conglomerate in Humboldt County, part of Cretaceous(?) and Tertiary rocks of Kleinhampl and Ziony (1967) in northern Nye County, and part of "older clastic rocks" of Tschanz and Pampeyan (1970) in Lincoln County
Continental sedimentary rocks (Late Cretaceous to Early Miocene)
CONTINENTAL SEDIMENTARY ROCKS-Clark County
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
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
Horse Spring Formation (Late Oligocene to Middle Miocene)
HORSE SPRING FORMATION-Tuffaceous sedimentary rocks, southern Nevada
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 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, 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
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, 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.
Sandy and silty limestone, conglomerate, and siltstone (Pennsylvanian to Late Permian)
SANDY AND SILTY LIMESTONE, CONGLOMERATE, AND SILTSTONE (Upper Pennsylvanian to Upper Permian)-Includes units such as Strathearn Formation of Dott (1955) and Buckskin Mountain, Beacon Flat, and Carlin Canyon Formations of Dott (1955)
Sedimentary rocks (Late Cretaceous to Oligocene)
SEDIMENTARY ROCKS-Includes Sheep Pass Formation (Eocene) and related units and unnamed tuffaceous sedimentary rocks
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 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 (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?).
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.
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.
Slaven Chert (Devonian)
SLAVEN CHERT-Chert and sparse limy sandstone, siltstone, and limestone. Lander County
Tuffaceous sedimentary rocks (Late Eocene to Late Miocene)
TUFFACEOUS SEDIMENTARY ROCKS-Locally includes minor amounts of tuff
Volcanogenic sedimentary rocks, tuff, andesite and felsitic flows, and carbonate rocks (Permian to Jurassic (?))
VOLCANOGENIC SEDIMENTARY ROCKS, TUFF, ANDESITIC AND FELSITIC FLOWS, AND CARBONATE ROCKS-Age uncertain. Mineral, Esmeralda, and Northwest Nye Counties
New York
Beekmantown Group (Lower Ordovician)
Beekmantown Group - Mohawk Valley: Chuctanunda Creek Dolostone; Tribes Hill Formation-limestone, dolostaone; Gailor Dolostone. Washington County: Providence Island Dolostone; Fort Cassin Formation-limestone, dolostone; Fort Ann Formation-limestone, dolostone; Cutting Formation-dolostone, local chert, limestone at top, siltstone at base.
Beekmantown Group (in part) (Lower Ordovician)
Beekmantown Group (in part) - In St. Lawrence Valley: Ogdensburg Dolostone (Beauharnois Dolostone in Canada); In Champlain Valley: Providence Island Dolostone; Fort Cassin Formation-limestone, dolostone; Fort Ann Formation (Spellman of Clinton and Essex Counties)-limestone, dolostone; Cutting Formation-dolostone (locally cherty), limestone, siltstone. In Vermont: includes Bridport, Bascom, Cutting, and Shelburne carbonates.
Brunswick Formation, undivided (Upper Triassic)
Brunswick Formation, undivided - includes the units: TRbg: sandstone and conglomerate; TRbs: sandstone, siltstone, mudstone; TRba: mudstone, sandstone, and arkose.
Cashaqua and Middlesex Shales (Upper Devonian)
Cashaqua and Middlesex Shales.
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.
Copake and Rochdale Formations (Lower Ordovician)
Copake and Rochdale Formations - Copake Formation-limestone, dolostone, siltstone; Rochdale Formation-limestone, dolostone; Halcyon Lake Dolostone-locally cherty.
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.
Medina Group (Lower Silurian)
Medina Group - Grimsby Formation-sandstone, shale.
Monmouth Group, Matawan Group and Magothy Formation (Upper Cretaceous)
Monmouth Group, Matawan Group and Magothy Formation - silty clay, glauconitic sandy clay, sand, gravel.
Normanskill Formation (Middle Ordovician)
Normanskill Formation - shale, argillite, siltstone.
Nunda Formation, West Hill Formation (Upper Devonian)
Nunda Formation, West Hill Formation - Nunda: sandstone, shale; West Hill: shale, siltstone; Corning Shale.
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.
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.
Raritan Formation (Upper Cretaceous)
Raritan Formation - clay, silty clay, sand, gravel.
Schenectady Formation (Upper Ordovician)
Schenectady Formation - graywacke, sandstone, siltstone, shale.
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.
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.
Ohio
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.
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.
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.
Oklahoma
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.
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)
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)
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)
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)
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)
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.
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
Holly Creek Formation (Phanerozoic | Mesozoic | Cretaceous-Early )
McALESTER TEXARKANA- Gravel, composed mostly of quartz and novaculite, with clay and silt, tan to red-brown; unconformable on Ouachita rocks; thickness, 30 to 100 feet, thickening to 1,070 feet in subsurface of southern McCurtain County
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."
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.
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.
Pleistocene and Pliocene deposits, undifferentiated (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene)
TEXAS- Interfingering beds, tongues, and lenses of sand, silt, clay, gravel, sandstone, caliche, limestone, conglomerate, and volcanic ash. Includes Ogallala and Laverne Formations of Pliocene age and younger deposits of Pleistocene age. Locally the units are tightly cemented by calcium carbonate; other places, they are very poorly consolidated and nearly free of cementing materials. Thickness ranges from 0 to about 800 feet.
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.
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)
Savanna + McAlester + Hartshorne + Atoka Formations (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle)
TULSA- "Savanna, McAlester, Hartshorne, and Atoka Formations," shale, sandstone, siltstone, limestone, and coal.
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
Oregon
Alluvial deposits (Holocene) (Holocene)
Sand, gravel, and silt forming flood plains and filling channels of present streams. In places includes talus and slope wash. Locally includes soils containing abundant organic material, and thin peat beds
Glaciofluvial, lacustrine, and pediment sedimentary deposits (Holocene and Pleistocene) (Pleistocene)
Unconsolidated, poorly sorted silt, sand, and gravel. Includes lacustrine deposits west of Columbia River Gorge (Trimble, 1963). Mostly in northern Morrow and Umatilla Counties where unit represents deposits of swollen late Pleistocene Columbia River (Hogenson, 1964)
Lacustrine and fluvial sedimentary rocks (Pleistocene) (Pleistocene)
Unconsolidated to semiconsolidated lacustrine clay, silt, sand, and gravel; in places includes mudflow and fluvial deposits and discontinuous layers of peat. Includes older alluvium and related deposits of Piper (1942), Willamette Silt (Allison, 1953; Wells and Peck, 1961), alluvial silt, sand, and gravel that form terrace deposits of Wells and others (1983), and Gresham and Estacada Formations of Trimble (1963). Includes deltaic gravel and sand and gravel bars, in pluvial lake basins in southeastern part of map area. In Rome Basin, includes discontinuous layers of poorly consolidated conglomerate characterized by well-rounded, commonly polished pebbles of chert and pebbles and cobbles of quartzite. In places contains mollusks or vertebrate fossils indicating Pleistocene age; mostly deposits of late Pleistocene age, but locally includes some deposits of early Holocene age. Includes Touchet Beds of Flint (1938), deposits of valley terraces of Newcomb (1965), and, in southeast Oregon, basin-filling deposits that incorporate Mazama ash deposits (Qma, Qmp) in the youngest layers
Loess (Holocene and Pleistocene) (Pleistocene to Holocene)
Windblown clayey silt and fine sand. Includes the Pleistocene Palouse Formation and deposits derived mostly from reworking of Palouse Formation. Contains local interbedded layers of soil, caliche, and some water-laid silt and gravel
Marine facies (Middle Eocene to Late Eocene)
Basaltic clastic rocks and pillow lavas, locally mapped separately by Wells and others (1983). Foraminiferal assemblages are assigned to the lower part of the Narizian Stage of Mallory (1959); see Wells and others (1983) for summary
Marine facies (Middle Eocene to Late Eocene)
Basaltic clastic rocks and pillow lavas, locally mapped separately by Wells and others (1983). Foraminiferal assemblages are assigned to the lower part of the Narizian Stage of Mallory (1959); see Wells and others (1983) for summary
Nonmarine sedimentary rocks (Eocene) (Eocene)
Continentally derived conglomerate, pebble conglomerate, sandstone, siltstone, and mudstone containing abundant biotite and muscovite. Dominantly nonvolcanic; clastic material derived from underlying older rocks
Playa deposits (Holocene) (Holocene)
Clay, silt, sand, and some evaporites
Siletz River Volcanics and related rocks (middle and lower Eocene and Paleocene) (Paleocene to Middle Eocene)
Aphanitic to porphyritic, vesicular pillow flows, tuff-breccias, massive lava flows and sills of tholeiitic and alkalic basalt. Upper part of sequence contains numerous interbeds of basaltic siltstone and sandstone, basaltic tuff, and locally derived basalt conglomerate. Rocks of unit pervasively zeolitized and veined with calcite. Most of these rocks are of marine origin and have been interpreted as oceanic crust and seamounts (Snavely and others, 1968). Foraminiferal assemblages referred to the Ulatisian and Penutian Stages (Snavely and others, 1969); K-Ar ages range from 50.7 +/- 3.1 to 58.1 +/- 1.5 Ma (Duncan, 1982); includes the lower part of the Roseburg Formation of Baldwin (1974), which has yielded K-Ar ages as old as 62 Ma
Terrace, pediment, and lag gravels (Holocene and Pleistocene) (Pleistocene to Holocene)
Unconsolidated deposits of gravel, cobbles, and boulders intermixed and locally interlayered with clay, silt, and sand. Mostly on terraces and pediments above present flood plains. Includes older alluvium of Smith and others (1982) in the Klamath Mountains and both high- and low-level terraces along Oregon coast. Includes dissected alluvial fan deposits northeast of Lebanon, and Linn and Leffler Gravels of Allison and Felts (1956)
Tillamook Volcanics (upper and middle Eocene) (Middle Eocene to Late Eocene)
Subaerial basaltic flows and breccia and submarine basaltic breccia, pillow lavas, lapilli and augite-rich tuff with interbeds of basaltic sandstone, siltstone, and conglomerate. Includes some basaltic andesite and, near the top of the sequence, some dacite. Potassium-argon ages on middle and lower parts of sequence range from about 43 to 46 Ma (Magill and others, 1981): one potassium-argon age from dacite near top of sequence is about 40 Ma (see Wells and others, 1983)
Tuffaceous sedimentary rocks, tuffs, pumicites, and silicic flows (Miocene) (Miocene)
Moderately well indurated lacustrine and fluvial (flood-plain) deposits of tuff, pumicite, palagonite tuff, and lesser siltstone, arkosic sandstone, and pebble and cobble conglomerate. Locally contains some lignite beds. Former glass in silicic vitroclastic debris commonly crystallized and altered to secondary silica minerals, alkali feldspar, zeolites, and clay minerals. Contains some welded and nonwelded ash-flow tuffs, and minor rhyolite flows. Widespread and abundant vertebrate fossils and minor plant fossils indicate that most of unit is of middle Miocene (Barstovian) age; parts of unit between Goose Lake and Warner Valley may include rocks of early Miocene age. Locally interlayered with and locally overlies basalt and andesite flows of unit Tmb. Overlies and locally interfingers with Picture Gorge Basalt (Thayer and Brown, 1966) and with Miocene basalt south of Prineville. Includes Mascall Formation of Merriam (1901), Sucker (Succor) Creek Formation of Corcoran and others (1962) and Kittleman and others (1967), Drip Spring Formation of Kittleman and others (1965, 1967), Trout Creek Formation of Smith (1926), and "rocks of Miocene age" of Malde and Powers (1962) in the southern Owyhee Upland province. In southeast Oregon, some of these rocks represent caldera and moat-fill deposits
Yaquina Formation (lower Miocene and upper Oligocene) (Late Oligocene to Early Miocene)
Thick- to thin-bedded sandstone, conglomerate, and tuffaceous siltstone of deltaic origin; locally contains thin coal and ash beds. Conglomerate contains abundant clasts of pumice and dacitic volcanic rocks. In places includes thick lenses of marine tuffaceous siltstone and fine-grained sandstone. Foraminifers in formation assigned to the Zemorrian and lower part of the Saucesian Stages of Kleinpell (1938) and molluscan fauna to the lower Blakeley Stage of Weaver and others (1944)
Pennsylvania
Allentown Formation (Cambrian)
Allentown Formation - Medium- to medium-dark-gray, thick-bedded dolomite and impure limestone; dark-gray chert stringers and nodules; laminated; oolitic and stromatolitic; some orange-brown-weathering calcareous siltstone at base.
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.
Bryn Mawr Formation (Tertiary)
Bryn Mawr Formation - High-level terrace deposits; reddish-brown gravelly sand and some silt. Age uncertain.
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.
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.
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.
Gettysburg conglomerate (Triassic)
Gettysburg conglomerate - Gray quartz conglomerate, sandstone, and red siltstone and mudstone.
Gettysburg Formation (Triassic)
Gettysburg Formation - Reddish-brown to maroon, silty mudstone and shale containing thin red sandstone interbeds; several thin beds of impure limestone.
Hamilton Group (Devonian)
Hamilton Group - Includes, in descending order, the Mahantango (Dmh) and Marcellus (Dmr) 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 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.
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 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.
Pensauken and Bridgeton Formations, undifferentiated (Tertiary)
Pensauken and Bridgeton Formations, undifferentiated - Dark-reddish-brown, cross-stratified, feldspathic quartz sand and some thin beds of fine gravel and rare layers of clay or silt.
Pleasant Hill Formation (Cambrian)
Pleasant Hill Formation - Gray, thin-bedded, argillaceous limestone interbedded with shale, siltstone, and sandstone.
Poplar Gap and Packerton Members of Catskill Formation, undivided (Devonian)
Poplar Gap and Packerton Members of Catskill Formation, undivided - Includes, in descending order, the Poplar Gap (Dcpg) and Packerton (Dcp) Members of the Catskill Formation.
Poplar Gap Member of Catskill Formation (Devonian)
Poplar Gap Member of Catskill Formation - Gray and light-olive-gray sandstone, conglomerate, and siltstone containing intermittent red beds; laterally equivalent to Clarks Ferry, Sawmill Run, and Berry Run Members.
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.
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.
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.
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.
Trenton Gravel (Quaternary)
Trenton Gravel - Gray or pale-reddish-brown, very gravelly sand interstratified with crossbedded sand and clay-silt beds; includes areas of Holocene alluvium and swamp deposits.
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.
Rhode Island
Conanicut Group - East Passage Formation (Cambro-Ordovician)
Conanicut Group - East Passage Formation - Red, orange-brown, and gray-green phyllite and thinly-bedded, nongraded sandstone and siltstone; rare limestone, and sparse volcanic rock including welded-tuff.
Narragansett Bay Group - Pondville Conglomerate (Pennsylvanian)
Narragansett Bay Group - Pondville Conglomerate - Gray to greenish conglomerate with sand-sized matrix, interbedded with quartz arenite and litharenite; typically lenticular and discontinuous. At type locality (Pondville Station, Massachusetts), unit consists of interbedded red and green slate, siltstone, arkose, and quartzite-pebble conglomerate.
South Carolina
Alluvial Valley Swamp (Quaternary)
Alluvial Valley Swamp: Unconformable on all underlying units, fluvial sand and gravel at base, grading upwards into fine sands and silts, local peat. May be overrun with recent sediments from forest cutting and agriculture.
Tidal Marsh (Quaternary)
Tidal Marsh: Peat and muck deposits along tidal margins of esturaries and back bays. Deposits range from a few feet to 60+ feet deep. Locally include silt and fine sand and clay as levees on tidal channels. At depth peaty material may be accumulated from fresh water plants. Peat at the surface dominated by spartina and other salt tolerant species.
South Dakota
Alluvium (Phanerozoic | Cenozoic | Quaternary)
Clay to boulder-size clasts with locally abundant organic material. Thickness up to 75 ft (23m).
Clayely Till, Ground Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Pre-Illinoian])
Heterogeneous, clay to boulder-size clasts of glacial orgin. Exhibits a distinctive weathered, dissected surface. Contains prominent oxidized joints and fractures with gypsum or calcite. Typically overlain by up to 45 ft (14 m) of loess. Thickness of uppermost Pre-Illinoian till may be up to 120 ft (37 m). Composite thickness of all Pre-Illinoian till may be up to 1,000 ft (305 m).
Colluvium (Phanerozoic | Cenozoic | Quaternary)
Clay to boulder-size clasts forming rubble residuum and talus. Thickness up to 30 ft (9m).
Eolian Deposits (Phanerozoic | Cenozoic | Quaternary)
(loess and sand dune) Silt to medium-grained sand. Deposited as sand sheets and barchan, linear, and dome-like dunes and as veneer on uplands. Thickness up to 300 ft (91m).
Gravel Deposits (Phanerozoic | Cenozoic | Tertiary )
Clay to boulder-size clasts primarily from igneous and metamorphic rocks of the central Black Hills. Also includes Phanerozoic lithic clasts and rare vertebrate fossils. Thickness up to 60 ft (18 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).
Java Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Early)
Sand to gravel of fluvial orgin. Upper portion is tan to reddish-brown eolian silt with minor clay and fine-grained sand. Thickness up to 180 ft (55 m).
Lacustrine Sediments (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Glaciolacustrine clay and silt with minor sand and gravel. Forms flat, low-lying terrain. Includes deposits from Glacial Lake Dakota and Glacial Lake Agassiz. Thickness up to 60 ft (18m).
Lacustrine Sediments, Ice-walled (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Glaciolacustrine clay and silt with minor sand and gravel. Forms elevated level terrain. Thickness up to 60 ft (18m).
Outwash, Terrace (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous clay to gravel of glaciofluvial orgin. Thickness up to 60 ft (18m)
Outwash, Undifferentiated (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous sand and gravel, with minor clay and silt. Deposits of glaciofluvial orgin including outwash plains, kame terraces, and other undifferentiated deposits. Thickness up to 30 ft (9m).
Outwash, Valley Train (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous silt to gravel. Confined to valleys of glaciofluvial orgin. Thickness up to 60 ft (18m).
Pahasapa Limestone, Englewood Formation, Whitewood Limestone, Winnipeg Formation, and Deadwood Formation (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian(?) Devonian(?) Carboniferous Mississippian)
Note: see individual descriptions
Terrace Deposits (Phanerozoic | Cenozoic | Quaternary)
Clay to boulder-size clasts deposited as pediments, paleochannels, and terrace fills of former flood plains. Thickness up to 75 ft (23m).
Till, End Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by elevated linear ridges with hummocky terrain locally at former ice sheet margins. Composite thicknessof all Upper Wisconsin till may be up to 300 ft (91 m).
Till, Ground Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Illinoian(?)])
Heterogeneous, clay with silt to boulder-size clasts. Exhibits a distinctive weathered, dissected surface. Contains prominent oxidized joints and fractures with gypsum or calcite. Typically overlain by up to 25 ft (8 m) of loess. Thickness up to 120 ft (37 m).
Till, Ground Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by smooth, rolling terrain. Composite thickness of all Upper Wisconsin till may be up to 300 ft (91 m).
Till, Minor Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by elevated linear ridges including minor, washboard, or recessional moraines. Composite thicknessof all Upper Wisconsin till may be up to 300 ft (91 m).
Till, Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. Exhibits a distinctive weathered, dissected surface.Typically overlain by up to 10 ft (3m) of loess. Thickness up to 150 ft (46 m).
Till, Stagnation Moraine (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Upper Wisconsin])
Heterogeneous, clay with silt to boulder-size clasts of glacial orgin. A geomorphic feature that is characterized by hummocky terrain with abundant sloughs resulting from stagnation of ice sheets. Composite thickness of all Upper Wisconsin till may be up to 300 ft (91 m).
Tongue River Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene )
White, gray, and tan, massive, cross-bedded sandstone with interbedded gray, brown, and green claystone, bentonitic claystone, clayely siltstone, carbonate concretions, and lignite. Thickness up to 285 ft (87 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
Alluvial deposits (Quaternary)
Alluvial Deposits - Sand, silt, clay, and gravel. As much as 60 feet thick in flood plains of Tennessee and Cumberland Rivers; in smaller streams generally less than 20 feet thick.
Alluvial deposits (Quaternary)
Alluvial Deposits - Sand, silt, clay, and gravel. In flood plain of Mississippi River more than 100 feet thick; in smaller streams generally less than 20 feet thick.
Alluvial deposits (Quaternary)
Alluvial Deposits - Sand, silt, clay and gravel. Mapped only in valley of Cumberland River and in Elk Valley. Thickness generally less than 30 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.
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.
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, 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.
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, 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 270 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.
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.
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.
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.
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.
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.
High-level alluvial deposits (Quaternary-Tertiary)
High-level Alluvial Deposits - Iron-stained gravel, sand, silt, and clay; variable in thickness but generally less then 60 feet thick.
High-Level Alluvial Deposits (Quaternary-Tertiary)
High-Level Alluvial Deposits - Iron-stained gravel, sand, silt, and clay; variable in thickness but generally less than 60 feet thick.
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.
Jackson (?) Formation (Tertiary)
Jackson (?) Formation - Sand, with layers of gray clay, silt, and lignite. Exposed only in bluffs along Mississippi River; thickness at least 60 feet.
Loess (Quaternary)
Loess - Clayey and sandy silt, gray to brown, massive. Maximum thickness about 100 feet along bluffs of Mississippi River; thins eastward. (Minimum mapped thickness 4 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.
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.
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 (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, 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.
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.
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.
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 (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.
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.
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.
Tuscaloosa Formation (Cretaceous)
Tuscaloosa Formation - Poorly sorted, light-gray chert gravel in a matrix of silt and sand; locally interbedded with sand and clay lenses. Thickness 0 to 140 feet.
Tuscaloosa Formation (Cretaceous)
Tuscaloosa Formation - Poorly sorted, light-gray chert gravel in a matrix of silt and sand; locally interbedded with sand and clay lenses. Thickness 0 to 150 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 300 to 375 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.
Texas
alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene)
alluvium
Alluvium in Rio Grande, subdivided into areas predominantly of clay (Phanerozoic | Cenozoic | Quaternary | Holocene)
Alluvium in Rio Grande, subdivided into areas predominantly of clay
Alluvium in Rio Grande, subdivided into areas predominantly of sand (Phanerozoic | Cenozoic | Quaternary | Holocene)
Alluvium in Rio Grande, subdivided into areas predominantly of sand
Archer City Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp])
Archer City Formation
barrier island deposits (Phanerozoic | Cenozoic | Quaternary)
barrier island deposits
barrier ridge and barrier flat deposts (Phanerozoic | Cenozoic | Quaternary | Holocene)
barrier ridge and barrier flat deposts
Beaumont Formation, areas predominantly clay (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late)
Beaumont Formation, areas predominantly clay
Beaumont Formation, areas predominantly sand (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late)
Beaumont Formation, areas predominantly sand
Bell Canyon, Cherry Canyon, and Brushy Canyon Formations undivided (Phanerozoic | Paleozoic | Permian [Guadalupe])
Bell Canyon, Cherry Canyon, and Brushy Canyon Formations undivided
Blackwater Draw Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
Blackwater Draw Formation
bolson deposits (Phanerozoic | Cenozoic | Tertiary | Pliocene)
bolson deposits
bolson deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
bolson deposits
Bouquillas Formation (Phanerozoic | Mesozoic | Cretaceous-Late)
Bouquillas Formation
Buda Limestone and Del Rio Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Late)
Buda Limestone and Del Rio Clay, undivided
Campagrande Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
Campagrande Formation
clay dune (Phanerozoic | Cenozoic | Quaternary | Holocene)
clay dune
Clear Fork Group (Phanerozoic | Paleozoic | Permian [Leonard])
Clear Fork Group
Deweyville Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene (?))
Deweyville Formation
Deweyville Formation with higher level? (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene (?))
Deweyville Formation with higher level?
dune sand sheet deposits (Phanerozoic | Cenozoic | Quaternary | Holocene)
dune sand sheet deposits
fill and spoil (Phanerozoic | Cenozoic | Quaternary | Holocene)
fill and spoil
Gatuna Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle(?))
Gatuna Formation
Harpersville Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Virgil])
Harpersville Formation
high gravel deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
high gravel deposits
Jackson Group, undivided (Phanerozoic | Cenozoic | Tertiary | Eocene Oligocene)
Jackson Group, undivided
Lingos Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle(?) Pleistocene-Late(?) Holocene)
Lingos Formation
Lissie Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle)
Lissie Formation
Llanoria Quartzite (preCambrian-Proterozoic [Grenville])
Llanoria Quartzite
Malone Formation (Phanerozoic | Mesozoic | Jurassic-Late)
Malone Formation
Manning Formation (Phanerozoic | Cenozoic | Tertiary | Eocene)
Manning Formation
Manning, Wellborn, and Cadell Formations, undivided (Phanerozoic | Cenozoic | Tertiary | Eocene)
Manning, Wellborn, and Cadell Formations, undivided
Munn Formation (Phanerozoic | Paleozoic | Permian [Guadalupe])
Munn Formation
Ogallala Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene Miocene)
Ogallala Formation
older alluvial deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
older alluvial deposits
Permian rocks, undivided (Phanerozoic | Paleozoic | Permian)
Permian rocks, undivided
playa deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
playa deposits
pond deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
pond deposits
Presidio Formation (Phanerozoic | Mesozoic | Cretaceous-Early [Aptian Albian])
Presidio Formation
Quaternary-Tertiary bolson deposits (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene)
Quaternary-Tertiary bolson deposits
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
sand deposits, undivided (Phanerozoic | Cenozoic | Quaternary | Holocene)
sand deposits, undivided
sand dune deposits (Phanerozoic | Cenozoic | Quaternary | Holocene)
sand dune deposits
sand sheet deposits (Phanerozoic | Cenozoic | Quaternary | Holocene)
sand sheet deposits
silt sheet (Phanerozoic | Cenozoic | Quaternary | Holocene)
silt sheet
Sparta Sand (Phanerozoic | Cenozoic | Tertiary | Eocene)
Sparta Sand
Tahoka Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Wisconsinan])
Tahoka Formation
Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene)
Terrace deposits
Tule Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
Tule Formation
unnamed Pliocene deposits (Phanerozoic | Cenozoic | Tertiary | Pliocene)
unnamed Pliocene deposits
Waggoner Ranch Formation (Phanerozoic | Paleozoic | Permian [Leonard])
Waggoner Ranch Formation
Whitsett Formation (Phanerozoic | Cenozoic | Tertiary | Eocene Oligocene)
Whitsett Formation
Wilberns Formation showing Point Peak, Morgan Creek Limestone, and Welge Sandstone Members, undivided (Phanerozoic | Paleozoic | Cambrian-Furongian)
Wilberns Formation showing Point Peak, Morgan Creek Limestone, and Welge Sandstone Members, undivided
Willis Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene)
Willis Formation
Wolfe City Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian])
Wolfe City Formation
Yucca Formation (Phanerozoic | Mesozoic | Cretaceous-Early)
Yucca Formation
Utah
Cambrian quartzite in Logan-Huntsville Allochthon (Early to Middle Cambrian)
Cretaceous (1) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Early Cretaceous)
Cretaceous (3) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Late Cretaceous)
Devonian sedimentary rocks in Logan-Huntsville Allochthon (Devonian)
Devonian sedimentary rocks in western Utah (Devonian to Mississippian)
Quaternary Lake Bonneville deposits (Quaternary)
Tertiary (3) sedimentary rocks in central Utah (Late Eocene to Early Oligocene)
Tertiary (3) sedimentary rocks in Uinta Mountains-Uinta Basin region (Middle Eocene to Early Oligocene)
Triassic (1) sedimentary rocks in Salt Lake City-Coalville-Randolph region (Early Triassic)
Triassic (1) sedimentary rocks in Salt southeastern Utah (Early Triassic)
Triassic (2) sedimentary rocks in southeastern Utah (Late Triassic)
Triassic (2) sedimentary rocks in southwestern Utah (Late Triassic)
Upper Cambrian carbonate rocks in Logan-Huntsville Allochthon (Middle Cambrian to Early Ordovician)
Younger Precambrian metamorphic rocks in Uinta Mountains-Uinta Basin region (Proterozoic Y)
Virginia
Bacons Castle Formation (Tertiary)
Bacons Castle Formation - Poorly sorted sand and laminated sand; clay and silt.
Bacons Castle Formation (Tertiary)
Bacons Castle Formation - Gravel grading upward into sand and sandy clayey silt
Bluefield Formation (Mississippian)
Bluefield Formation - Calcareous shale and limestone.
Charles City Formation (Quaternary)
Charles City Formation - Interbedded sand, silt, clay and minor gravel; at altitudes to 70-80 ft. (top of unit).
Chesapeake Group (Tertiary)
Chesapeake Group - Fine- to coarse-grained sand, silt, clay; variably shelly and diatomaceous
Chuckatuck Formation (Quaternary)
Chuckatuck Formation - Interbedded gravel, sand, silt, clay, and minor peat; at altitudes to 50-60 ft. (top of unit).
Elbrook Formation (Cambrian)
Elbrook Formation - Dolomite, shale, and minor limestone.
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, 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?)
Lower Tertiary Deposits (Tertiary)
Lower Tertiary Deposits - Glauconitic quartz sand and clay-silt, shelly in part, minor sandy limestone and limey sand; may include the following formations: Brightseat, Aquia, Marlboro, Nanjemay, and Piney Point (Pamunkey Group); and Old Church.
Marsh and Intertidal Mud Deposits (Quaternary)
Marsh and Intertidal Mud Deposits - Organic-rich clay and silt
Martinsburg and Oranda Formations (Ordovician)
Martinsburg and Oranda Formations - Shale, sandstone, siltstone, and limestone.
Miocene Sand and Gravel (Tertiary)
Miocene Sand and Gravel - Sandy gravel, sand, silt, and clay.
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
Moorings Unit of Oaks and Coch (1973) (Tertiary)
Moorings Unit of Oaks and Coch (1973) - Sand, silt, and clay; at altitudes from 100-130 ft. (top of unit).
Mount Rogers Formation - Conglomerate, graywacke, laminated siltstone, and shale. (Proterozoic Z)
Mount Rogers Formation - Conglomerate, graywacke, laminated siltstone, and shale.
Nolichucky and Maryville Formations, Rogersville Shale, and Rutledge Formation (Cambrian)
Nolichucky and Maryville Formations, Rogersville Shale, and Rutledge Formation - Calcareous shale, limestone, and dolomite.
Omar Formation - Accomack Member: (Quaternary)
Omar Formation - Accomack Member: sand, gravel, silt, clay, and peat; at altitudes to 50 ft.
Pennington Group (Mississippian)
Pennington Group - Shale, sandstone, dusky-red mudstone, conglomerate, siltstone, and limestone.
Pliocene Sand and Gravel (Tertiary)
Pliocene Sand and Gravel - Sandy gravel, gravelly sand, poorly to well-sorted sands, and thin- to medium-beds of clay and silt, at altitudes from 170-320 ft. (top of unit).
Potomac Formation (Cretaceous)
Potomac Formation - Pebbly, poorly sorted quartzo-feldspathic sand interbedded with sandy clay and silt; minor organic-rich clay and silt
Price Formation (Mississippian)
Price Formation - Sandstone, conglomeratic sandstone, and shale with carbonaceous partings and impure coal beds.
Quaternary and Tertiary Deposits (Tertiary-Quaternary)
Quaternary and Tertiary Deposits - Tabb through Windsor Formations and alluvial/tidal prism deposits.
Shirley Formation (Quaternary)
Shirley Formation - Interbedded gravel, sand, silt, clay, and peat; at altitudes to 35-45 ft. (top of unit).
Silurian and Upper Ordovician Formations Undivided (Ordovician-Silurian)
Silurian and Upper Ordovician Formations Undivided - Includes: Skrt, Sm, Oun, Ous, Ou, Om. (Shrc and Okpl?)
Tabb Formation (Quaternary)
Tabb Formation - Undifferentiated. Includes the Poquoson Member (Qtp), Lynnhaven Member ( Qtl) and Sedgefield Member (Qts).
Tabb Formation: Lynnhaven and Poquoson Members (Quaternary)
Tabb Formation: Lynnhaven and Poquoson Members - Undifferentiated Qtl, Qts.
Tabb Formation; Lynnhaven Member (Quaternary)
Tabb Formation; Lynnhaven Member - Pebbly and cobbly sand grading upward into muddy, fine sand and silt, at altitudes to 15-18 ft. (top of unit).
Tabb Formtaion; Poquoson Member (Quaternary)
Tabb Formtaion; Poquoson Member - Pebbly sand grading upward into muddy, fine-grained sand and sandy silt, at altitudes to 11 ft. (top of unit).
Upper and Middle Ordovician Formations Undivided (Ordovician)
Upper and Middle Ordovician Formations Undivided - Includes: Oun, Ous, Ou, Om, Okpl, Oeln, Oml, Ols.
Windsor Formation (Tertiary-Quaternary)
Windsor Formation - Interbedded gravel, sand, silt, and clay; at altitudes to 85-95 ft. (top of unit).
Vermont
Middlebury and Chazy Limestone, Undifferentiated Youngman and Carman Formations, Day Point Member (Ordovician)
Middlebury and Chazy Limestone, Undifferentiated Youngman and Carman Formations, Day Point Member - Calcareous quartz sandstone, and calcarenite; orange-weathered dolomitic siltstones are common in eastern areas.
Northfield Formation (Devonian - Silurian)
Northfield Formation - Dark gray to black quartz-sericite slate or phyllite with fairly widely-spaced interbeds a few inches thick of siltstone and silty crystalline limestone like that of the Waits River Formation; calcareous slate north of Lamoille River; phyllite passes into gray quartz-sericite schist containing abundant porphyroblasts of biotite and garnet in southern Vermont.
Washington
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.
Cretaceous nonmarine rocks (Late Cretaceous)
Redbeds of thick-bedded sandstone, shale, and pebble conglomerate in upper Methow River area of Okanogan County.
Eocene volcanic rocks (Eocene )
Predominantly andesite flows and breccia; includes interbedded sedimentary rocks south of Startup in Snohomish and King Counties.
Mesozoic-Tertiary marine rocks, undivided (Miocene to Eocene)
Dark-gray, massive to poorly bedded gray-wacke of the interior Olympic Peninsula; commonly with interbedded slate, argillite, volcanic rocks, and minor arkosic sandstone. Includes rocks both older and younger than Ev2, some of which may be Paleozoic.
Mesozoic volcanic rocks, undivided (Jurassic)
Includes latite, andesite and basalt flows, tuff, and agglomerate. Interbedded sedimentary rocks in Orient area of Stevens County.
Miocene volcanic rocks (Middle Miocene)
Dark-gray to black, dense aphanitic basalt flows; commonly columnar jointed, less commonly irregularly and platy jointed; some flows vesicular, grading to scoriaceous; includes minor pillow lava, palagonite beds, and interbedded soil profiles and sedimentary beds; contains diatomite beds locally. Maximum thickness in south-central Washington may be in excess of 10,000 feet; much thinner in western Washington, where flows are mostly associated with marine sedimentary rocks. Includes acidic and intermediate volcanic rocks in northern Cascade Mountains.
Oligocene nonmarine rocks (Oligocene)
Andesite conglomerate, tuff beds, and mudflow material. Includes some interbedded andesite flows in Columbia River Gorge. Lake sediments with Oligocene flora in Republic area in Ferry County. Massive tuffaceous sandstone and siltstone with beds of coal and high-alumina clay in Castle Rock-Toledo coal district in Cowlitz and Lewis Counties; include local interbedded basalt flows and some marine and late Eocene rocks.
Ordovician rocks (Middle Ordovician)
Mainly black to gray slate or slaty argillite, argillite, black to dark-gray siltstone in north-central Stevens County and grayish olive-green silty argillite in west-central Stevens County. Many occurrences of Early and Middle Ordovician graptolites; also rare conodonts.
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.
Permian rocks (Permian-Triassic)
Conglomerate, graywacke, siltstone, argillite and interbedded fossiliferous limestone, greenstone, and minor angular conglomerate in northwestern Stevens and Ferry Counties. Impure quartzite, sandstone, graywacke, greenstone, ribbon chert, chert breccia, and limestone in Snohomish County and on San Juan Island. Lower Permian limestone on Black Mountain in northwestern Whatcom County. Middle Permian rocks in northeastern Washington.
Precambrian (?) phyllite (Cambrian-Precambrian boundary)
Mostly phyllite with interbedded carbonate rocks, quartzite, and gritstone; some tufflike beds and conglomerate at the base. Rocks confined to northeastern Pend Oreille County and central Stevens County.
Pre-upper Eocene rocks (Eocene (Olympic Peninsula); Cretaceous(?) (Yakima County))
Argillite and graywacke between inner and outer volcanic belts in Olympic Peninsula. Sheared carbonaceous argillite, argillite, graywacke, and minor conglomerate lenses and altered lava flows in western Yakima County.
Pre-Upper Jurassic metamorphic rocks of the low-grade zone (Jurassic)
Greenschist, phyllite, and slate; includes some limestone, quartzose phyllite, schistose metaconglomerate, breccia, and basic igneous rocks. Includes schist 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.
Triassic sedimentary rocks, undivided (Triassic with Permian where impossible to differentiate)
Predominantly limestone, marble, and dolomite near Riverside in Okanogan County. Conglomerate, shale, graywacke, gritstone, and limestone on San Juan Island. Siltstone with greenstone locally on Orcas Island. Graywacke conglomerate, cherty greenstone, and limestone in northern Ferry County.
Upper Eocene volcanic rocks (Late Eocene)
Predominantly andesite flows and breccia; includes some basalt flows. Contains basaltic conglomerate, pyroclastic rocks, tuff beds, and sandstone in Chehalis-Centralia coal district, Lewis 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 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)
Andesite and basalt flows and associated breccia in central Lewis County. Pyroclastic rocks, mudflows, flow breccia, and volcanic-rich sedimentary rocks in King and Pierce Counties.
Upper Jurassic-Lower Cretaceous sedimentary and volcanic rocks (Late Jurassic-Early Cretaceous)
Predominantly sedimentary rocks. Graywacke, argillite, and siltstone with some slate and phyllite; includes graywacke breccia and ribbon chert with minor local limestone lenses and basalt flows.
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 Tertiary volcanic rocks, undivided (Miocene-Oligocene)
Mostly massive andesite flows, flow breccia, and pyroclastic material; includes some basalt flows and sedimentary rocks.
West Virginia
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.
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.
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.
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.
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.
Wyoming
Basalt flows and intrusive igneous rocks (Phanerozoic | Cenozoic | Quaternary | Pleistocene)
BASALT FLOWS AND INTRUSIVE IGNEOUS ROCKS. Yellowstone area--Includes Osprey, Madison River, Swan Lake Flat, and Falls River Basalts, basalts of Mariposa Lake, Undine Falls Basalt, and gravels, sands, silts, and basalts of The Narrows. In and adjacent to Absaroka and Washakie Ranges--Includes basalt of Lava Mountain (age about 0.5 Ma).
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).
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.
Upper Miocene Rocks (Phanerozoic | Cenozoic | Tertiary | Miocene-Late)
UPPER MIOCENE ROCKS--Southwest Wyoming: South end of Wind River Range--Siliceous, arkosic, and locally radioactive sandstone, claystone, and conglomerate. Fission-track age about 27 Ma. Recent work suggests that part of these deposits may be of Eocene age. Pliocene and Miocene (as originally defined 2) South Pass Formation. Saratoga Valley--White to greenish-gray tuffaceous sandstone, siltstone, and claystone; locally conglomeratic. North Park Formation; Central Wyoming: Arkosic sandstone, conglomerate, and siltstone; some light-colored tuffaceous radioactive claystone and white cherty limestone. North of Sweetwater River in Granite Mountains--Light-colored tuffaceous radioactive claystone, siltstone, sandstone, and arkose. Moonstone Formation; East Wyoming: Light-colored tuffaceous claystone, sandstone, and conglomerate. Ogallala Formation in Denver Basin.

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