Geologic units in Oklahoma (state in United States)

Additional scientific data in this geographic area

Terrace Deposits (Pleistocene) at surface, covers 12 % of this area

WOODWARD- Lenticular and interfingering deposits of light-tan to gray gravel, sand, silt, clay, and volcanic ash. Sand dunes are common in many places. Thickness ranges up to 150 feet and averages about 60 feet. ENID- Sand, silt, clay, and gravel. Maximum thickness, about 75 feet (23 m) along major streams. TULSA- Fine gravel, sand, silt, and clay. CLINTON- Stream-laid deposits of sand, silt, clay, gravel, and volcanic ash; thickness ranges from 0 to about 120 feet. OKLAHOMA CITY- Lenticular beds of sand, silt, clay, and gravel. Thickness ranges from a few feet to about 100 feet and probably averages about 50 feet along major streams. FORT SMITH- Gravel, sand, silt, and clay. LAWTON- Sand, clay, and gravel as much as 75 feet (23 m) in Tillman County, ranging from 5 to 50 feet (2 to 15 m) elsewhere. ARDMORE-SHERMAN- Gravel, sand, silt, clay, and volcanic ash; thickness, about 5 to 50 feet; at various levels, as high as 160 feet above present flood plains. McALESTER TEXARKANA- Gravel, sand, silt, clay, and volcanic ash; several levels 20 to 160 feet or more above present flood plains, with each level containing deposits that average 20 to 30 feet in thickness, some windblown sand on top; may include colluvial wash down sides of hills.

Alluvium (Holocene) at surface, covers 10 % of this area

WOODWARD- Lenticular and interfingering deposits of gravel, sand, silt, and clay. Generally light-tan to gray. Thickness along major streams ranges up to 100 feet and probably averages 40 feet; along minor streams the thickness ranges up to 45 feet and probably averages 20 feet. ENID- Sand, silt, clay, and locally gravel. Maximum thickness ranges from 30 to 80 feet (9 to 24 m) along major streams and from 0 to 60 feet (0 to 18 m) along minor streams. TULSA- Gravel, sand, silt, and clay. TULSA- Gravel, sand, silt, and clay. OKLAHOMA CITY- Sand, silt, clay, and lenticular beds of gravel. Thickness ranges from about 30 to 100 feet and probably averages about 50 feet along major streams. Along minor streams, thickness ranges from a few feet to about 50 feet and probably averages about 25 feet. LAWTON- Sand, clay, and gravel as much as 50 feet (15 m) thick; Shown only along major streams and tributaries. ARDMORE-SHERMAN- Gravel, sand, silt, and clay, including low terraces; thickness, about 25 to 100 feet. McALESTER TEXARKANA- Gravel, sand, silt, and clay, including low terraces about 30 feet above channels; thickness, about 50 feet along Little River and 110 feet along Red River.

Ogallala Formation (Pliocene) at surface, covers 6 % of this area

CIMARRON- Generally semiconsolidated clay, silt, sand, gravel, and caliche 0 to 400 feet thick. BEAVER- Interbedded sand, siltstone, clay, gravel lenses, and thin limestone. Caliche common near surface but occurrence is not limited to the surface. Caliche accounts for most of the white color in the Ogallala. Other colors generally light tan or buff but locally may be pastel shades of almost any color. The Laverne and Rexroad Formations of Pliocene age and the Meade Group and Odee (of local usage) and other formations of Pleistocene age occur locally and are included with the Ogallala Formation, 0-700 feet thick. WOODWARD- Gravel, sand, silt, clay, caliche, and limestone, locally cemented with calcium carbonate. Generally light-tan to gray to white. Thickness ranges up to 400 feet and probably averages 150 feet. CLINTON- Gray to light-brown, fine- to medium-grained sand with some, clay, silt, gravel, volcanic ash, and caliche beds; locally cemented by calcium carbonate. Thickness ranges from 0 to about 320 feet. The formation thins eastward.

Garber Sandstone (Early Permian) at surface, covers 5 % of this area

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.

Wellington Formation (Early Permian) at surface, covers 4 % of this area

ENID- Mostly red-brown shale to north, grading into fine-grained sandstone and mudstone conglomerate southward into Logan County. Thickness, about 850 feet (260 m). (Sumner Group) OKLAHOMA CITY- Red-brown shale and orange-brown fine-grained sandstone, containing much maroon mudstone conglomerate and chert conglomerate to south. Thickness ranges from about 150 feet in south to 500 feet in north. (Sumner Group) LAWTON- Maroon shale, about 130 feet (40 m) thick, with greenish-gray and black sandstone of the "Ryan Sandstone Bed" at base. (Sumner Group). ARDMORE-SHERMAN- Shale, red-brown, with several 20- to 30-foot bituminous sandstones at base ("Ryan"); thickness, about 100 to 200 feet, decreasing southeastward.

Rush Springs Formation (Early Permian) at surface, covers 4 % of this area

WOODWARD- Orange-brown fine-grained sandstone, commonly crossbedded, with some interbedded red-brown shale, silty shale, and gypsum beds. In southern part of area, about 30 feet below top is a thin massive gypsum bed ("Weatherford Bed" or "One Horse Bed"), not mapped here. About 100 feet lower is another thin gypsum bed ("Old Crow Bed") not mapped here. Thickness is about 190 feet in southern part and 90 feet near Kansas border, with top eroded in many places. CLINTON- "Rush Springs Formation," Pr, orange-brown, cross-bedded, fine-grained sandstone with some dolomite and gypsum beds. Thickness, about 300 feet, thinning northward to about 186 feet. LAWTON- "Rush Springs Formation," Pr, very fine-grained, cross-bedded sandstone, 136 to 300 feet (41 to 90 m) thick. The "Weatherford Gypsum Bed," Prw, contains gypsum and dolomite and is as much as 60 feet (18 m) thick in the upper part of the Rush Springs. (Whitehorse Group) ARDMORE-SHERMAN- Sandstone, orange-brown, fine- to medium-grained, moderately indurated, with "Weatherford Gypsum Bed," Prw, 2 to 15 feet thick, near top. Thickness, about 280 feet, top eroded (Whitehorse Group).

Oscar Group (Late Pennsylvanian) at surface, covers 3 % of this area

ENID- Mainly shale with many layers of limestones that pinch out southward, where fine-grained arkosic sandstones are thicker and more numerous. Near Kansas border, sequence is (descending): "Herington Limestone" (20 feet thick) at top, "Enterprise Shale" (45 feet thick), "Winfield Limestone, "IPowi (8 feet thick), "Gage Shale" (80 feet thick), "Towanda Limestone" (3 feet thick), "Holmesville Shale" (25 feet thick), "Fort Riley Limestone," IPofr (30 feet thick) and underlying Florence Flint, IPofr (8 feet thick), "Blue Springs Shale" (60 feet thick), "Kinney Limestone" (5 feet thick), "Wymore Shale" (22 feet thick), "Wreford Limestone," IPowr (25 feet thick), "Speiser Shale" (38 feet thick), "Funston Limestone (4 feet thick), "Blue Rapids Shale" (15 feet thick), "Crouse Limestone" (6 feet thick), "Easly Creek Shale" (12 feet thick), "Bader Limestone" (5 feet thick), "Stearns Shale" (10 feet thick), "Morrill Limestone" (2 feet thick), "Florena Shale" (6 feet thick), "Cottonwood Limestone," IPoc (3 feet thick), "Eskridge Shale" (6 feet thick), and "Neva Limestone" (25 feet thick) at base. Total thickness, about 400 feet. OKLAHOMA CITY- Red-brown to gray shale and orange-brown fine-grained, crossbedded sandstone; grades southward into arkosic sandstone and conglomerate. Includes "Herington Limestone" at top inPayne County, "Neva Limestone" (0.2 to 1.2 feet thick) at basein Lincoln County, and "Hart Limestone" (4 to 10 feet thick)at base in Pottawatomie County. In Payne County, includesthin stringers of "Winfield Limestone," IPowi (75 feet belowtop), "Fort Riley Limestone," IPofr (245 feet below top),"Wreford Limestone," IPowr (345 feet below top), and"Cottonwood Limestone," IPoc (525 feet below top). Thickness ranges from 300 feet in south to 600 feet in north. LAWTON- Shale, sandstone, and arkose, 300 to 500 feet (90 to 150 m) thick, base covered. ARDMORE-SHERMAN- Shale, red-brown to gray, with arkosic sandstones and limestone conglomerates near Arbuckle Mountains; "Hart Limestone" at base; thickness, 300 to 500 feet, decreasing southeastward. (Pontotoc Group).

Keokuk and Reeds Spring Formations and St. Joe Group (Early Mississippian) at surface, covers 3 % of this area

TULSA- "Keokuk Formation," chert and limestone. "Reeds Spring Formation," chert and limestone. "St. Joe Group," limestone and shale. FORT SMITH- Mkr "Keokuk Formation," chert; "Reeds Spring Formation," chert and limestone; and "St. Joe 'Group,'" limestone and marlstone.

Pleistocene and Pliocene deposits, undifferentiated (Pleistocene to Pliocene) at surface, covers 3 % of this area

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.

Boggy Formation (Middle Pennsylvanian) at surface, covers 2 % of this area

TULSA- Shale, sandstone, and coal. FORT SMITH- Shale, sandstone, and coal; includes Bluejacket Sandstone Member at base. ARDMORE-SHERMAN- Shale and sandstone, blue-gray to brown, fine- to coarse- grained, with some thin limestone lenses and a coal bed 2.5 feet thick about 400 feet above base. Thickness, 1,250 to 2,800 feet. "Bluejacket Sandstone," IPbj, at base, 8 to 12 feet thick, with 2-foot "Secor coal" 50 feet above top of Bluejacket. (Lower Franks Conglomerate) McALESTER TEXARKANA- Shale, brown, to blue-gray, illitic, chloritic, with many sandstones, fine- to coarse-grained, micaceous, quartzose, moderately to well-indurated, with "Secor coal" about 50 feet above base; thickness, 2,140 to 4,000 feet, increasing eastward.

Hennessey Group (Early Permian) at surface, covers 2 % of this area

CLINTON- Reddish-brown shale with some thin, greenish-gray siltstone and orange-brown sandstone and siltstone beds; thickness, about 500 feet. The "Hennessey Group" is not subdivided in the southern part of the Clinton quadrangle; in the northeastern corner of the quadrangle, the upper part of the "Bison Formation," Pbi, is exposed as orange-brown and greenish-gray, fine-grained sandstone and siltstone. The Bison is gradational southward into reddish-brown shale; it thins southward and is about 120 feet thick. LAWTON- "Hennessey Group," Phy, reddish-brown to gray shale with some tan sandstones, 130 to 200 feet (40 to 60 m) thick (locally unconformable on Cambrian igneous rocks).

Cloud Chief Formation (Late Permian) at surface, covers 2 % of this area

WOODWARD- Red-brown and greenish-gray shale and siltstone with some orange-brown fine-grained sandstone and siltstone. At base are two or more thin, pink to maroon to greenish-gray dolomite beds and (or) gypsum beds ("Moccasin Creek Bed") eroding into a mappable escarpment. About 25 feet above the base is a white to light-gray dolomite ("Day Creek Bed") not mapped. Thickness ranges up to 160 feet, with top eroded in many places. CLINTON- Reddish-brown to orange-brown shale, interbedded with siltstone and sandstone in the middle part and some dolomite and much gypsum in lower part; thickness about 400 feet, thinning northward to about 175 feet. The "Moccasin Creek Gypsum Member" is at the base. LAWTON- Represented in this area by the "Moccasin Creek Gypsum Member," which is about 30 feet (9 m) thick.

Atoka Formation (Middle Pennsylvanian) at surface, covers 2 % of this area

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.

Vanoss Group (Late Pennsylvanian) at surface, covers 2 % of this area

ENID- Alternating layers of limestone and shale to north, grading southward into limestone, shale, and fine-grained arkosic sandstone. Locally group contains thin coal seams. Near Kansas border, group includes (descending): "Salem Point Shale" (12 feet thick) at top, underlain by "Burr Limestone" (8 feet thick), "Legion Shale" (4 feet thick), "Sallyards Limestone" (3 feet thick), "Roca Shale" (15 feet thick), "Red Eagle Limestone," IPvre (20 feet thick), "Johnson Shale" (35 feet thick), "Long Creek Limestone," IPvlc (10 feet thick), unnamed shale (3 feet thick), "Hughes Creek Limestone (15 feet thick), unnamed shale (12 feet thick), "Americus Limestone, "IPvam, (12 feet thick), "Oaks Shale" (3 feet thick), "Houchen Creek Limestone (8 feet thick), "Stine Shale" (20 feet thick), "Five Point Limestone" (3 feet thick), unnamed shale (12 feet thick), "Brownville Limestone, IPvb (8 feet thick), "Pony Creek Shale" (40 feet thick), "Grayhorse Limestone," IPvg (5 feet thick), unnamed shale (12 feet thick), "Nebraska City Limestone" (5 feet thick), "French Creek Shale" (12 feet thick), "Jim Creek Limestone" (3 feet thick), "Friedrich Shale" (30 feet thick), "Grandhaven Limestone" (2 feet thick), "Dry Shale" (25 feet thick), "Dover Limestone" (30 feet thick), "Willard-Langdon Shale" (110 feet thick), "Elmont Limestone," IPve (10 feet thick), "Stonebreaker Shale" (20 feet thick), and "Reading Limestone" (20 feet thick) at base. Total thickness, about 500 feet (150 m). OKLAHOMA CITY- Red-brown to gray shale and orange-brown fine-grained, crossbedded sandstone; grades southward into arkosic sandstoneand conglomerate. Includes many thin limestone beds and shale units north of North Canadian River descending): "Roca Shale"(75 feet thick), "Red Eagle Limestone," IPvre (3 to 8 feetthick), "Johnson Shale" (60 feet thick), "Long Creek Limestone," IPvlc (9 to 12 feet thick), "Hughes Creek Shale" (52 feet thick), "Americus Limestone," IPva (1.0 to 2.5 feetthick), "Admire Shale" (70 feet thick), "BrownvilleLimestone," IPvb (1 to 3 feet thick), "Pony Creek Shale" (75 feet thick), "Grayhorse Limestone," IPvg (1 foot thick), unnamed shale (70 feet thick), "Elmont Limestone," IPve (1.2to 7.8 feet thick), "Stonebreaker Shale" (60 feet thick), and"Reading Limestone" (1.5 feet thick), at base. Totalthickness of group ranges from 250 feet in south to 490 feet in north. ARDMORE-SHERMAN- Shale, maroon, arkose, and limestone conglomerate; thickness, 250 to 900 feet (subsurface), decreasing southward. (Pontotoc Group).

Senora Formation (Middle Pennsylvanian) at surface, covers 2 % of this area

TULSA- Shale with thin and lenticular sandstone, minor limestone, and coal. OKLAHOMA CITY- Mainly fine-grained micaceous sandstone and shale locally containing coal beds. Thickness ranges from about 500 to 950 feet. FORT SMITH- Shale, sandstone, and thin coal seams. ARDMORE-SHERMAN- Shale, gray, and light-brown medium-grained sandstone; thickness, 150 to 500 feet, decreasing southwestward. Subdivided into lower sandstone, 350 feet thick, and upper shale, 150 feet thick.

Antlers Sand or Antlers Sandstone (Early Cretaceous) at surface, covers 2 % of this area

ARDMORE-SHERMAN- "Antlers Sand" Sand, white to yellow, medium-grained, weakly indurated, with varicolored clays. Contains arkosic conglomerates near Arbuckle Mountains and "Baum Limestone" near Mannsville anticline. Thickness, 200 to 700 feet. McALESTER TEXARKANA- "Antlers Sandstone" Sandstone and sand, white to reddish-yellow to orange-brown to gray, fine- to coarse-grained, quartzose, crossbedded, moderately to weakly indurated, interbedded with varicolored clays and conglomerates; contains fossil wood and dinosaurs; rests unconformably upon Ouachita rocks but conformably upon DeQueen Limestone; thickness, 0 to 320 feet, thickening southeastward to 900 feet in subsurface.

Flowerpot Shale (Early Permian) at surface, covers 2 % of this area

WOODWARD- Red-brown silty shale with some thin gypsum and dolomite beds in upper 50 feet and fine-grained sandstones in upper part to north. The middle and upper parts contain 50 feet or more of rock salt in the immediate subsurface, giving origin to the Ferguson Salt Plain in Blaine County and the Big and Little Salt Plains in Woods and Harper Counties on the Cimarron River. Thickness ranges from 180 feet in north part to 430 feet in south part. The "Chickasha Formation" (Pc) is a deltaic tongue of red-brown to greenish-gray to orange-brown cross-bedded mudstone conglomerate, siltstone, shale, and fine-grained sandstone, about 30 feet thick, in the middle of the Flowerpot Shale, pinching out northward. CLINTON- "Flowerpot Shale," Pf, reddish-brown shale containing several salt and gypsum beds in the upper part. Thickness, about 300 to 450 feet; gradational southward and eastward into Chickasha Formation and Duncan Sandstone. OKLAHOMA CITY- Mostly red-brown silty clay shale with stringers of gypsum (satin spar and selenite); grades southward into "Chickasha Formation". Thickness, 20 to 40 feet. (El Reno Group) LAWTON- "Flowerpot Shale," Pf, reddish-brown and greenish-gray shale, interbedded with greenish-gray siltstone; thickness, about 175 to 195 feet (53 to 59 m).

Vamoosa Group or Vamoosa Formation (Late Pennsylvanian) at surface, covers 2 % of this area

ENID- "Vamoosa Group"- Alternating layers of shale and fine- to coarse-grained sandstone, with some thin limestones. Sandstone layers are thicker, coarser grained, and more numerous southward. Group near Kansas border includes (descending): unnamed shale and sandstone (160 feet thick) at top, "Plattsmouth Limestone, "IPvap (14 to 23 feet thick), unnamed shale and sandstone (15 to 90 feet thick), "Leavenworth Limestone," IPvale (4 feet thick), unnamed shale and sandstone (170 feet thick) "Labadie Limestone," IPval (6 to 23 feet thick; may also be called "Haskell Limestone"), unnamed shale and sandstone (60 to 100 feet thick), "Bowring Limestone," IPvab (2 feet thick; may also be called "Westphalia Limestone"), unnamed shale (5 to 10 feet thick), and basal "Cheshewalla Sandstone (7 to 20 feet thick; also called "Tonganoxie Sandstone"). Total thickness about 630 feet (190 m) OKLAHOMA CITY- "Vamoosa Formation"- Alternating thin to massive layers of fine- to coarse-grained sandstone and sandy, silty shale containing some chert conglomerate in middle and lower parts of formation. Thickness ranges about 200 to about 690 feet. ARDMORE-SHERMAN- "Vamoosa Formation"- Shale, sandstone, and chert conglomerate; red-brown to buff fine- to coarse-grained sandstone. Subdivided into 12 members, each with coarse clastics at base overlain by shale. Thickness, about 125 to 260 feet (to 1,000 feet in subsurface), decreasing southward.

Jackfork Group or Jackfork Sandstone (Early Pennsylvanian) at surface, covers 2 % of this area

ARDMORE-SHERMAN- "Jackfork Sandstone"- Sandstone, gray, white, and tan, coarse-grained, cherty, with gray shale and some boulders up to 7 feet in diameter; thickness 1,150 to 5,000 feet Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- "Jackfork Group"- Sandstone, tan to gray, fine- to coarse-grained, quartzose, with some mica, poorly to well-indurated, quartzitic has some gray shale and several maroon shales; black, white-speckled "Chickasaw Creek Chert" is at base; thickness, 1,500 to 6,000 feet or more. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT.

Stanley Group or Stanley Shale (Mississippian) at surface, covers 1 % of this area

ARDMORE-SHERMAN- "Stanley Shale"- Shale, dark-gray, siliceous,with some gray to buff fine-grained sandstones; thickness,10,000 feet Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- "Stanley Group"- Shale, olive-green to gray, illitic, chloritic, with many5- to 30-foot-thick beds of poorly sorted, micaceous, quartzose sandstones and some thin siliceous cherty beds and black shales; several tuff beds occur in basal 1,000 feet and are indicated by red line in Stanley exposures as designated on map; many asphaltite, lead, and quartz veins occur along fault zones; mostly Chesterian age; thickness, 7,500 to 14,000 feet or more. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT.

McAlester and Hartshorne Formations (Middle Pennsylvanian) at surface, covers 1 % of this area

TULSA- "McAlester and Hartshorne Formations", shale and some sandstone and coal. FORT SMITH- IPmh "McAlester" and "Hartshorne Formations" (undifferentiated), shale, sandstone, and coal.

Marlow Formation (Early Permian) at surface, covers 1 % of this area

WOODWARD- Orange-brown fine-grained sandstone and siltstone, with some interbedded red-brown shale and silty shale in upper part and some thin gypsum beds at base, about 35 feet above base, and at top. The upper two gypsum and (or) dolomite beds are generally pink to maroon and less than 1 foot thick; they may erode into mappable escarpments about 20 feet apart, being named "Emanuel Bed" at top (mapped) and "Relay Creek Bed" 15 to 20 feet below the top (not mapped). In places the basal Marlow is a greenish-gray medium-grained sandstone. In Woods and Woodward Counties, the "Doe Creek Lentil" (Pmd) is a coarse-grained calcareous sandstone with algal clumps and invertebrate fossils, ranging up to 70 feet thick from the base of the Marlow to the Relay Creek Bed, cropping out in a narrow band of high hills striking northeast. Thickness is about 120 feet, with top eroded at many places. CLINTON- "Marlow Formation," Pm, orange-brown, fine-grained sandstone and siltstone, about 100 to 130 feet thick, thinning northward. This formation has 2 gypsum and (or) dolomite beds in upper 20 feet--the "Emanuel Bed" (at top) and the "Relay Creek Bed" (20 feet below top). Two thin, pale shales occur; the first is 1 foot below the top ("Gracemont") and the second is 55 feet above the base (unnamed). OKLAHOMA CITY- Mostly orange-brown fine-grained gypsiferous sandstone, with some red-brown shale. Contains 10 feet of calcitic sandstone lenses near middle and 2 thin dolomites (or gypsums) at top. Exposed thickness, about 50 feet (top 50 to 75 feet eroded). (Whitehorse Group) LAWTON- "Marlow Formation," Pm, very fine-grained sandstone with some silty shale; thickness, about 90 to 130 feet (27 to 40 m); contains 2 thin gypsum and (or) dolomite beds in upper 20 feet (6 m)-the "Emanuel Bed" (at top) and the "Relay Creek Bed" (20 feet below top). (Whitehorse Group) ARDMORE-SHERMAN- Sandstone, orange-brown, fine- to medium-grained, moderately indurated, with "Verden Sandstone Lentil," Pmv, 10 feet thick near middle, and "Relay Creek" and "Emanuel" dolomite and gypsum beds at top; thickness, 105 to 135 feet (Whitehorse Group).

Dog Creek Shale (Early Permian) at surface, covers 1 % of this area

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).

Savanna Formation (Middle Pennsylvanian) at surface, covers 1 % of this area

TULSA- "Savanna Formation," shale and thin sandstone, limestone, and coal. FORT SMITH- IPsa "Savanna Formation," shale, sandstone, and coal ARDMORE-SHERMAN- Sandstone and shale, gray to brown, fine- to coarse-grained, cherty, with several thin coal seams near middle; thickness, 1,120 to 1,600 feet (Lower Franks Conglomerate) McALESTER TEXARKANA- Shale, tan to brown, illitic, chloritic, and sandstone, fine-to coarse-grained, micaceous, quartzose, with several thin coal seams in middle, one of which is "Cavanal coal;" thickness, 1,470 to 2,000 feet, increasing eastward.

Duncan Sandstone (Early Permian) at surface, covers 1 % of this area

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).

Lynn Mountain Formation (Early Pennsylvanian) at surface, covers 1 % of this area

McALESTER TEXARKANA- Shale, gray to tan, with many fine- to coarse-grained, quartzose, micaceous sandstone with many bottom markings; top eroded; thickness, 3,000 to 7,000 feet or more; unconformable upon Goddard, Delaware Creek, Woodford, and older beds that are exposed north and west of Ti Valley Fault. Occurs in the OUACHITA MTNS.

Ada Group or Ada Formation (Late Pennsylvanian) at surface, covers 1.0 % of this area

ENID- "Ada Group"- Mainly shale with many limestone layers that are thinner and pinch out southward, where fine-grained sandstones are thicker and more numerous. Near Kansas border, group includes (descending): "Auburn shale" (50 feet thick) at top, underlain by "Wakarusa Limestone," IPaw (2 feet thick), unnamed shale (40 feet thick), "Rulo Limestone" (3 feet thick), unnamed shale (18 feet thick), "Happy Hollow Limestone" (2 feet thick), unnamed shale and sandstone (60 feet thick), "Bird Creek Limestone," IPab (2 feet thick; called "Church Limestone" in Kansas), "Severy-Aarde Shale" (70 feet thick), "Turkey Run Limestone," IPat (2 feet thick; called "Coal Creek Limestone" in Kansas), unnamed shale (30 feet thick), "Pearsonia Limestone" (3 feet thick), unnamed shale (15 feet thick), "Little Hominy Limestone" (22 feet thick), "Deer Creek Limestone (15 feet thick), unnamed shale (10 feet thick), "Plummer Limestone" (2 feet thick), unnamed shale (35 feet thick), and "Beil Limestone Member" (10 feet thick) of "Lecompton Limestone" at base. Total thickness, about 400 feet (120 m). OKLAHOMA CITY- "Ada Group"- Mostly orange-brown fine-grained sandstone and red-brown to gray shale; grades southward into chert conglomerates. Includes the following thin limestone beds and shale units north of North Canadian River (descending): "Auburn Shale" (80 feet thick), "Wakarusa Limestone," IPaw (1 to 6 feet thick), unnamed shale (95 feet thick), "Bird Creek Limestone," IPab (1 to 9 feet thick), "Severy-Aarde Shale" (45 feet thick), "Turkey Run Limestone," IPat (1 foot thick), unnamed shale (45 feet thick), and "Lecompton Limestone" (1.5 to 10 feet thick), at base. Total thickness of group ranges from 100 feet in south to 280 feet in north. ARDMORE-SHERMAN- "Ada Formation"- (= Collings Ranch Conglomerate) Shale, red-brown to gray, bituminous sandstone, and limestone conglomerate; thickness, 100 to 1,400 feet (subsurface), decreasing southward.

Fairmont Shale (Early Permian) at surface, covers 1.0 % of this area

WOODWARD- Red-brown blocky shale with some greenish-gray calcitic siltstones. Thickness ranges up to 160 feet. ENID- Mainly red-brown shale with many thin layers of calcitic siltstone in upper 60 feet (18 m). Thickness, about 150 feet (45 m). (Hennessey Group) OKLAHOMA CITY- Red-brown blocky shale; grades into "Garber Sandstone" at base. Thickness, 30 feet at Oklahoma City, 110 feet near Purcell, and 120 feet near Kingfisher. (Hennessey Group) ARDMORE-SHERMAN- Shale, red-brown, blocky; thickness, 40 to 80 feet, decreasing southward. (Hennessey Group).

Woodford Shale (Late Devonian) at surface, covers 0.9 % of this area

ARDMORE-SHERMAN- Shale, black, fissile, cherty; thickness, 160 to 560 feet, increasing southward. Occurs in the ARBUCKLE MTNS.

Blaine Formation (Early Permian) at surface, covers 0.8 % of this area

WOODWARD- Alternating cyclic sequence of 3 or 4 massive gypsum beds with red-brown shales, generally with a named dolomite at the base of each gypsum, and a greenish-gray shale at the base of each dolomite. The named unmapped sequence is (ascending) "Cedar Springs Dolomite, Medicine Lodge Gypsum," shale, "Magpie Dolomite, Nescatunga Gypsum," shale, "Altona Dolomite, Shimer Gypsum," shale, and"Haskew Gypsum" at top. Thickness ranges up to 90 feet, with the shales being thinner northward. CLINTON- "Blaine Formation," Pb, 3 to 4 gypsum and dolomite beds, about 100 to 200 feet thick, separated by reddish-brown shale. Gradational southward and eastward into Chickasha Formation. OKLAHOMA CITY- Mostly thin gypsums with thin dolomites below each gypsum, interbedded with red-brown shale; grades southward into "Chickasha Formation". Thickness, 50 to 75 feet. (El Reno Group).

Dune Sand (Pleistocene) at surface, covers 0.8 % of this area

CIMARRON- Fine- to medium-grained sand 0 to 40 feet thick. TEXAS- Fine to coarse windblown sand. Maximum thickness about 30 feet. BEAVER- Fine to coarse, round to sub-round, windblown sand consisting mostly of quartz grains. 0-50 feet thick.

Doxey Formation or Doxey Shale (Late Permian) at surface, covers 0.8 % of this area

WOODWARD- "Doxey Formation"- Red brown shale and siltstone, with greenish-gray calcareous siltstone at base. Exposed thickness is 30 feet, with top eroded. CLINTON- "Doxey Shale"- Reddish-brown, silty shale and siltstone; thickness, about 190 feet.

Cedar Hill Sandstone (Early Permian) at surface, covers 0.8 % of this area

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).

Coffeyville and Checkerboard Formations or Checkerboard Limestone (Middle Pennsylvanian) at surface, covers 0.7 % of this area

ENID- "Coffeyville Formation" is mainly shale interbedded with fine-to medium-grained sandstone. Locally formation contains thin coal seams. Thickness ranges from 175 to 470 feet (50 to 140 m). Underlying "Checkerboard Limestone" is crystalline limestone 2 to 15 feet (1 to 5 m) thick. TULSA- "Coffeyville Formation," shale and thin-bedded sandstone. "Checkerboard Formation," limestone and some shale. OKLAHOMA CITY- "Coffeyville Formation," mainly shale interbedded with fine- to medium-grained sandstone locally containing chert and limestone conglomerate and thin coal seams; thickness, 150 to 470 feet. Underlying "Checkerboard Limestone," crystalline limestone 2.5 to 5 feet thick.

Bison Formation or Bison Shale (Early Permian) at surface, covers 0.7 % of this area

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).

Wewoka Formation (Middle Pennsylvanian) at surface, covers 0.7 % of this area

OKLAHOMA CITY- Interbedded fine- to medium-grained sandstone and calcareous shale. Thickness ranges from 400 to 750 feet. FORT SMITH- Shale, sandstone, and minor limestones ARDMORE-SHERMAN- Shale, blue-gray, sandstone, chert conglomerate, and limestone conglomerate; thickness, 400 feet.

Chickasha Formation (Early Permian) at surface, covers 0.6 % of this area

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).

Salt Plains Formation (Early Permian) at surface, covers 0.6 % of this area

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).

Nellie Bly Formation and Hogshooter Limestone (Middle Pennsylvanian) at surface, covers 0.5 % of this area

ENID- "Nellie Bly Formation" consists mainly of shale with a few layers of fine- to medium-grained sandstone. Thickness ranges from 80 to 550 feet (25 to 170 m). Underlying "Hogshooter Limestone" is massive crinoidal limestone 1 to 50 feet (0.3 to 14 m) thick. OKLAHOMA CITY- "Nellie Bly Formation," mainly shale with many fine-grained sandstone beds and limestone beds locally in upper part; thickness, about 250 to about 550 feet. Underlying"Hogshooter Limestone," massive crinoidal limestone 1 to 15 feet thick.

Seminole Formation (Middle Pennsylvanian) at surface, covers 0.5 % of this area

TULSA- Shale, sandstone, and thin coal beds. OKLAHOMA CITY- Chert conglomerate, shale, and fine-grained sandstone containing coal seams in upper part locally. Thickness ranges from 100 to 375 feet. FORT SMITH- Sandy shale, sandstone, and thin coal seams. ARDMORE-SHERMAN- Shale, gray-green, with buff fine-grained sandstones, chert conglomerates, and limy sandstones; thickness, about 120 feet. (Upper Franks Conglomerate).

Caddo Formation (Early Cretaceous) at surface, covers 0.5 % of this area

ARDMORE-SHERMAN-Limestones, marls, and shales; 150 feet thick. Subdivided into "Fort Worth Limestone" at top and "Duck Creek Limestone" below. McALESTER TEXARKANA- Limestones, white to cream, silty, alternating with gray shales, with "Texigryphaea washitaensis;" 7-foot bed at top (Fort Worth equivalent) and blue-gray silty shales and limestones below with "Texigryphaea navia" (Duck Creek equivalent); thickness, 150 feet. Ouachita Mountain uplift; S. OK folded belt province.

Wann and Iola Formations or Iola Limestone (Middle Pennsylvanian) at surface, covers 0.5 % of this area

ENID- "Wann Formation" consists of shale and fine- to medium-grained sandstone with many thin layers of fossiliferous limestone. Thickness ranges from 50 to 400 feet (15 to 122 m). "Iola Limestone" is mainly limestone, calcareous sandstone, and shale and underlies Wann. Thickness ranges 4 to 100 feet (1 to 30 m). TULSA- "Wann Formation," shale with thin sandstone and limestone. "Iola Formation," limestone and shale. OKLAHOMA CITY- "Wann Formation," shale and fine- to medium-grained sandstone; thickness, 40 to 180 feet. Underlying "Iola Limestone," mainly fine-grained calcareous sandstone and limestone with some shale; thickness, 15 to 20 feet.

Elk City Sandstone (Late Permian) at surface, covers 0.5 % of this area

CLINTON- Reddish-brown, fine-grained sandstone with minor amounts of silt and clay, weakly cemented by iron oxide, calcium carbonate, and gypsum; maximum thickness 185 feet, top eroded.

Alluvium (Holocene) at surface, covers 0.4 % of this area

CIMARRON- Clay, silt, sand, and gravel 0 to 100 feet thick. TEXAS- Sand, silt, clay, and gravel located in valleys of principal streams. Thickness not known but may exceed 100 feet in North Canadian River valley and may be 50 to 100 feet in lower parts of valleys of Coldwater and Palo Duro Creeks BEAVER - Sand, gravel, silt, and clay in discontinuous lenses along courses of larger streams. 0-50 feet thick.

Pitkin + Fayetteville + Batesville + Hindsville + Moorefield Formations (Late Mississippian) at surface, covers 0.4 % of this area

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.

McAlester Formation (Middle Pennsylvanian) at surface, covers 0.4 % of this area

ARDMORE-SHERMAN- Shale, gray, with "Upper Hartshorne coal" 1 to 50 feet above base, 500 to 600 feet thick; overlain by dark-gray shale with many buff fine-grained sandstones, 595 to 1,030 feet thick; overlain by dark-gray shale, 300 to 925 feet thick, with "McAlester coal," 1 to 3 feet thick, a few feet above base. Total thickness ranges from 1,150 to 2,420 feet. (Lower Franks Conglomerate). McALESTER TEXARKANA- Shale, gray, illitic, chloritic, with many tan to gray sandstones, fine- to coarse-grained, micaceous, quartzose; "McAlester and Stigler coals" 600 to 800 feet or more below top; thickness, 2,000 to 2,830 feet, increasing eastward.

Oolagah Formation (Middle Pennsylvanian) at surface, covers 0.4 % of this area

TULSA- Thin-bedded limestone and some shale in the southern part of the area. North of Oolagah, in western Rogers County, the map unit, IPol, includes the following formations: "Altamont Formation," limestone and minor shale; "Bandera Formation," shale and thin sandstone; "Pawnee Formation," limestone and minor shale.

Woodbine Formation (Late Cretaceous) at surface, covers 0.4 % of this area

McALESTER TEXARKANA- Sand, dark-green, yellowish-red, white, gray, fine- to coarse-grained, tuffaceous in upper part; crossbedded, quartzose, and brownish-red noncalcareous clay; some gravel lentils with little to no quartz and some lignites and fossil plants; rests unconformably upon successively older Cretaceous units eastward; thickness, 325 to 455 feet, increasing eastward.

Barnsdall Formation (Middle Pennsylvanian) at surface, covers 0.4 % of this area

ENID- Formation is mainly fine- to medium-grained sandstone, overlain by shale. At top is a thick shale, with "Okesa Sandstone Member" in middle and "Birch Creek Limestone" (called "South Bend Limestone") at base. Birch Creek extends southward from Kansas border to Township 23 N., where limestone grades into overlying Okesa Sandstone. South of Township 23 N., Okesa grades downward into underlying "Torpedo Sandstone" and underlying Wann Formation. Total thickness ranges from 45 to 200 feet (14 to 60 m). OKLAHOMA CITY- Mostly fine-grained sandstone overlain by shale; may grade northward into "Wann Formation". Thickness ranges from about 80 to 200 feet.

Calvin Sandstone (Middle Pennsylvanian) at surface, covers 0.4 % of this area

OKLAHOMA CITY- Medium-grained, thin-bedded to massive sandstone nd silty shale. Thickness ranges from 230 to about 440 feet. FORT SMITH- Shale and sandstone. ARDMORE-SHERMAN- Sandstone, brown, medium-grained, with some gray shale; thickness, 40 to 320 feet, thinner southward.

Tallant Formation (Middle Pennsylvanian) at surface, covers 0.3 % of this area

ENID- Alternating layers of shale and fine- to medium-grained sandstone. Thickness ranges from 75 to 250 feet (23 to 75 m). OKLAHOMA CITY- Mostly fine- to medium-grained sandstone 10 to 60 feet thick overlain by shale 25 to 65 feet thick. Cut out by ""Vamoosa Formation"" in central part of area. Total thickness ranges from 0 to 100 feet.

Purcell Sandstone (Early Permian) at surface, covers 0.3 % of this area

OKLAHOMA CITY- Red-brown to maroon fine- to coarse-grained sandstone, mudstone conglomerate, and red- brown shale. Thickness, 150 feet. (Hennessey Group). ARDMORE-SHERMAN- Sandstone, red-brown to maroon and greenish-gray, fine- to coarse-grained, with some shale and mudstone conglomerate; thickness, 90 to 150 feet, decreasing southward. (Hennessey Group).

Kingman Formation or Kingman Siltstone (Early Permian) at surface, covers 0.3 % of this area

WOODWARD- "Kingman Formation"- Orange-brown to greenish-gray fine-grained sandstone and siltstone, with some red-brown shale. Thickness is about 70 feet. ENID- "Kingman Siltstone"- Mainly red-brown with several thin layers of greenish-gray and orange-brown calcitic siltstone. Thickness, about 70 feet (20 m). (Hennessey Group). OKLAHOMA CITY- "Kingman Siltstone"- Orange-brown to greenish- gray, even bedded siltstones with some fine-grain sandstone and red-brown shale; grades southward into "Purcell Sandstone". Thickness, 30 feet. (Hennessey Group).

Van Vacter Member of Blaine Formation (Early Permian) at surface, covers 0.3 % of this area

LAWTON- "Van Vacter Member," Pbv, of the Blaine Formation contains 6 dolomite-gypsum-shale sequences with a total thickness of 80 to 105 feet (24 to 32 m).

Post Oak Conglomerate (Early Permian) at surface, covers 0.3 % of this area

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.

Dakota Sandstone (Early Cretaceous) at surface, covers 0.3 % of this area

CIMARRON- Buff to light-brown, fine- to medium-grained, thin bedded to massive sandstone with interbedded shales.

Holdenville Formation or Holdenville Shale (Middle Pennsylvanian) at surface, covers 0.3 % of this area

OKLAHOMA CITY- "Holdenville Shale"- Mainly clay shale with some interbedded fine-grained calcareous sandstone locally containing beds of crystalline limestone. Thickness ranges from 100 to 280 feet. FORT SMITH- "Holdenville Shale"- Shale, thin sandstone and minor limestones. ARDMORE-SHERMAN- "Holdenville Formation"- Shale, blue-gray, with light-brown sandstones and chert conglomerates and 2 prominent limestones--the upper, or "Sasakwa Limestone," white, fine-grained, 1 to 15 feet thick, 35 feet below the top, and the lower, or "Homer Limestone," dark-brown, sandy, 2 to 10 feet thick, 40 to 70 feet below the Sasakwa. Thickness, 210 to 260 feet. (Upper Franks Conglomerate).

Kiamichi Formation (Early Cretaceous) at surface, covers 0.2 % of this area

ARDMORE-SHERMAN- Shale, dark-gray, plastic, with oyster-shell limestones; thickness, about 30 feet. McALESTER TEXARKANA- Shale, dark-gray to black, with some brown fossiliferous limestones, with "Texigryphaea navia;" thickness, 28 to 36 feet, and up to 80 feet in subsurface of southern McCurtain County.Ouachita Mountain uplift; S. OK folded belt province.

Fort Scott Limestone (Middle Pennsylvanian) at surface, covers 0.2 % of this area

TULSA- Limestone and shale. (Mapped with the Labette Formation south of Bird Creek inTulsa County).

Bokchito Formation (Early Cretaceous) at surface, covers 0.2 % of this area

ARDMORE-SHERMAN- Clay, illitic, kaolinitic, with some tan limestones and sandstones. Subdivided into "Pawpaw Clay" at top, 40 to 60 feet thick; "Quarry Limestone," 13 feet thick; "Weno Clay," 100 to 135 feet thick; and basal "Denton Clay," 50 to 70 feet thick.

Bloyd and Hale Formations (Early Pennsylvanian) at surface, covers 0.2 % of this area

TULSA- "Bloyd Formation," limestone and shale. "Hale Formation," limestone and sandstone. FORT SMITH- IPbh "Bloyd Formation," shale and limestone; and "Hale Formation," limestone and sandstone.

Thurman Sandstone (Middle Pennsylvanian) at surface, covers 0.2 % of this area

OKLAHOMA CITY- Mainly medium-grained, silty sandstone with cherty conglomerate at base. Only a few feet exposed in quadrangle. FORT SMITH- Sandstone and shale. ARDMORE-SHERMAN- Sandstone, brown, fine- to coarse-grained, with some gray shale and basal 50-foot chert conglomerate; thickness, 80 to 250 feet, decreasing southwestward. McALESTER TEXARKANA- Sandstone, brown, fine- to coarse-grained, with some gray shale and a basal 50-foot chert conglomerate; grades northward into Boggy Formation; top eroded at many places; thickness, 200 feet.

Wichita Granite Group (Middle Cambrian) at surface, covers 0.2 % of this area

CLINTON- Pink, medium-grained granite; three outliers have been mapped in the southern part of quadrangle. LAWTON- Granites of various textures; thickness, 600 to 15,000 feet (180 to 4,570 m).

Dune Sand (Pleistocene) at surface, covers 0.2 % of this area

CLINTON- Wind-blown sand; thickness ranges from a thin Veneer to about 70 feet. LAWTON- Wind-laid sand; maximum thickness about 50 feet (15 m).

Nowata Formation (Middle Pennsylvanian) at surface, covers 0.2 % of this area

TULSA- Shale and minor sandstone and limestone.

Chanute Formation (Middle Pennsylvanian) at surface, covers 0.2 % of this area

ENID- Mainly fine-grained micaceous sandstone and coarse-grained, crossbedded sandstone separated by shale. Locally Chanute contains thin coal seams. Thickness ranges from about 10 to 150 feet (3 to 45 m). TULSA- Thin- to thick-bedded, fine- to coarse-grained sandstone and shale. OKLAHOMA CITY- Mainly fine- to medium-grained sandstone 3 to 20 feet thick, overlain by shale 20 to 80 feet thick. Total thickness ranges from about 25 to 90 feet.

Nellie Bly Formation (Middle Pennsylvanian) at surface, covers 0.2 % of this area

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.

Labette Formation (Middle Pennsylvanian) at surface, covers 0.2 % of this area

TULSA- Shale and thin sandstone and limestone.

Pitkin + Fayetteville + Hindsville + Moorefield Formations (Late Mississippian) at surface, covers 0.2 % of this area

FORT SMITH- Mp "Pitkin Formation," limestone; "Fayetteville Formation," shale and limestone; "Hindsville Formation," limestone and shale; and "Moorefield Formation," limestone.

Permian rocks undifferentiated (Late Permian to Early Permian) at surface, covers 0.2 % of this area

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.

Goodland Limestone and Walnut Clay (Early Cretaceous) at surface, covers 0.2 % of this area

ARDMORE-SHERMAN- "Goodland Limestone," limestone, gray, dense, nodular to massive; thickness, 20 to 30 feet. At base is "Walnut Clay," tan clay, about 4 feet thick. McALESTER TEXARKANA- Limestone, white, fine crystalline, massive-bedded, with "Texigryphaea mucronata;" some argillaceous buff beds in lower few feet may be "Walnut Clay" equivalents; erodes into a mappable escarpment; thickness, 26 to 55 feet.

Johns Valley Formation or Johns Valley Shale (Early Pennsylvanian) at surface, covers 0.2 % of this area

ARDMORE-SHERMAN- "Johns Valley Formation"- Shale, dark-gray, with boulder conglomerate; thickness, 425 to 900 feet. Occurs in the OUACHITA MNTS McALESTER TEXARKANA- "Johns Valley Shale"- Shale, dark-gray, with some stringers of Wapanucka-like limestone in northwestern part of area; contains exotic boulders of southern Arbuckle Mountain facies, ranging from Fort Sill to Goddard and as large as 369 feet in diameter; some Wapanucka nodules are not exotic but were formed in place; thickness, 300 to 1,000 feet. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT.

Whitehorse Group (Early Permian) at surface, covers 0.2 % of this area

CLINTON- Predominantly orange-brown, fine-grained sandstone, the "Whitehorse Group" is mapped as Pwh where separate formations have not been distinguished and as the "Rush Springs Formation" and the "Marlow Formation" where identified. "Rush Springs Formation," Pr, orange-brown, cross-bedded, fine-grained sandstone with some dolomite and gypsum beds. Thickness, about 300 feet, thinning northward to about 186 feet. The "Weatherford Gypsum Bed," Prw, is about 30 to 60 feet below the top (mapped in southeastern part only). "Marlow Formation," Pm, orange-brown, fine-grained sandstone and siltstone, about 100 to 130 feet thick, thinning northward. This formation has 2 gypsum and (or) dolomite beds in upper 20 feet--the "Emanuel Bed" (at top) and the "Relay Creek Bed" (20 feet below top). Two thin, pale shales occur; the first is 1 foot below the top ("Gracemont") and the second is 55 feet above the base (unnamed). The "Verden Sandstone Lentil," Pmv, is a coarse-grained, calcareous, fossiliferous sandstone (2 to 10 feet thick) that occurs in the middle of the Marlow, about 25 feet below the Relay Creek Bed and 85 to 95 feet above the base. LAWTON- Predominantly orange-brown, fine-grained sandstone, the "Whitehorse Group" is mapped as Pwh where separate formations have not been distinguished and as the "Rush Springs Formation" and the "Marlow Formation" where identified. "Whitehorse Group undifferentiated," Pwh, fine-grained sandstone and siltstone as much as 100 feet (30 m) thick in western part of quadrangle, interbedded with gypsum beds 3 to 10 feet (1 to 3 m) thick.

West Spring Creek Formation (Early Ordovician) at surface, covers 0.2 % of this area

ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained, gradational eastward into tan fine- to coarse-grained dolomite; some tan to gray sandstone and shale; thickness, 1,875 to 3,000 feet, decreasing eastward. (Arbuckle Group) Individual Fm description not found. Occurs in the ARBUCKLE MTNS.

West Spring Creek and Kindblade Formations (Early Ordovician) at surface, covers 0.1 % of this area

LAWTON- "West Spring Creek Formation" and "Kindblade Formation," Owk, dolomite, dolomitic sandstone, conglomerate, and limestone; thickness, approximately 2,000 feet (600 m). (Upper part of Arbuckle Group). ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained, gradational eastward into tan fine- to coarse-grained dolomite; some tan to gray sandstone and shale; thickness, 1,875 to 3,000 feet, decreasing eastward. (Arbuckle Group) Individual Fm description not found. Occurs in the ARBUCKLE MTNS.

Tokio Formation (Late Cretaceous) at surface, covers 0.1 % of this area

McALESTER TEXARKANA- Sand, light-gray, fine- to coarse-grained, quartzose, poorly sorted, crossbedded, and gray clay shale, with many cylindrical pipe structures, petrified wood and invertebrates; same as Bonham Marl and Austin Chalk of Texas; thickness ranges from 88 to 380 feet, increasing eastward; reaches thickness of 595 feet in subsurface southeastward.

Cool Creek and McKenzie Hill Formations (Early Ordovician) at surface, covers 0.1 % of this area

LAWTON- "Cool Creek Formation" and "McKenzie Hill Formation," Ocm, limestone and conglomerate with abundant quartz sand and cherty zones; thickness, approximately 2,000 feet (600 m). (Upper part of Arbuckle Group). ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained, cherty, gradational eastward into dolomites and sandstones; thickness, 1,500 to 2,300 feet, decreasing eastward. (Arbuckle Group) Occurs in the ARBUCKLE MTNS.

Tishomingo and Troy Granites (Middle Proterozoic) at surface, covers 0.1 % of this area

ARDMORE-SHERMAN- Granite, pink, with much microcline and biotite; "Troy" is fine grained; "Tishomingo" is coarse grained. Estimated thickness, 10 miles. (1.3 billion years old) Occurs in the ARBUCKLE MTNS.

Weatherford Gypsum Bed of Rush Springs Formation (Early Permian) at surface, covers 0.1 % of this area

CLINTON- The "Weatherford Gypsum Bed," Prw, dolomite and gypsum beds, is about 30 to 60 feet below the top (mapped in southeastern part only). LAWTON- "Weatherford Gypsum Bed," Prw, contains gypsum and dolomite and is as much as 60 feet (18 m) thick in the upper part of the Rush Springs. (Whitehorse Group) ARDMORE-SHERMAN- "Weatherford Gypsum Bed," Prw, 2 to 15 feet thick, near top of Rush Springs Formation.

Stuart Shale (Middle Pennsylvanian) at surface, covers 0.1 % of this area

OKLAHOMA CITY- Mostly laminated clay shale and minor amounts of silty sandstone. Thickness ranges from 80 to 180 feet. FORT SMITH- Shale and minor sandstone. ARDMORE-SHERMAN- Shale, blue to dark-gray, with some fine- to medium-grained brown sandstones; thickness, 80 to 300 feet, decreasing southwestward. McALESTER TEXARKANA- Shale, blue to dark-gray, with some fine- to medium-grained sandstones; top eroded; lower 20 feet exposed.

El Reno Group (Early Permian) at surface, covers 0.1 % of this area

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.

Elm Fork Member of Blaine Formation (Early Permian) at surface, covers 0.1 % of this area

LAWTON- "Elm Fork Member," Pbe, of the Blaine Formation contains 3 dolomite-gypsum sequences with a total thickness of 80 to 110 feet (24 to 34 m).

Dexter Member of Woodbine Formation (Late Cretaceous) at surface, covers 0.1 % of this area

ARDMORE-SHERMAN- sandstone, shale, and lignite, moderately to weakly indurated, about 100 feet thick.

Savanna + McAlester + Hartshorne Formations (Middle Pennsylvanian) at surface, covers 0.1 % of this area

TULSA- "Savanna, McAlester, and Hartshorne Formations," shale and some sandstone, limestone, and coal.

Morrison Formation (Late Jurassic) at surface, covers 0.1 % of this area

CIMARRON- Varicolored fine-grained sandstone, limestone, dolomite, shale, and conglomerate 0 to 470 +/- feet thick.

Bromide + Tulip Creek and McLish Formations (Middle Ordovician) at surface, covers 0.1 % of this area

ARDMORE-SHERMAN- Limestone, buff; shale, grayish-green; and sandstone, brown to white, fine- to medium-grained: approximate sequence of rocks in each formation, from top to bottom. Thickness, 750 to 1,400 feet, thinning eastward. (Simpson Group) Occurs in the ARBUCKLE MTNS.

Deese Group (Middle Pennsylvanian) at surface, covers 0.1 % of this area

ARDMORE-SHERMAN- Member of Glenn Fm, mainly massive sandstone, conglomerate and shale. Base of "Confederate Limestone" down to top of "Otterville Limestone;" thickness, 9,700 feet. Occurs in the ARDMORE BASIN.

Dewey Formation or Dewey Limestone (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

ENID- "Dewey Limestone"- Mainly medium-crystalline limestone and shale. Thickness ranges from 0 to 60 feet (0 to 18 m). TULSA- "Dewey Formation"- Limestone and some shale. (Mapped with the Chanute formation south of Bartlesville) OKLAHOMA CITY- "Dewey Limestone"- Mainly sandy limestone or calcareous sandstone containing limestone lenses 1.5 to 20 feet thick, overlain by shale 5 to 50 feet thick. Total thickness ranges from 20 to 60 feet.

Lewisville Member of Woodbine Formation (Late Cretaceous) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- mostly shale and weakly indurated sandstone, about 75 feet thick.

Arkansas Novaculite (Early Mississippian to Early Silurian) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Chert, fine- to very fine-grained, gray, green, tan, black, white, and pink, with interbedded black to gray shale in 1-to 18-inch beds; some interbedded conglomerates and in places a basal conglomerate; upper part has been determined to be Mississippian in age and lower part to be Early Silurian, on basis of examination of palynomorphs from Potato Hills; thickness, 600 feet or more. Occurs in the OUACHITA MTNS SOUTH OF TI VALLEY FAULT.

Red Branch Member of Woodbine Formation (Late Cretaceous) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- indurated sandstone, shale, and lignite, about 75 feet thick, erodes to an escarpment; and basal Dexter Member.

Purgatoire Formation (Early Cretaceous) at surface, covers < 0.1 % of this area

CIMARRON- Kiowa Shale Member: Gray to black fossiliferous shale with sandstone in the upper part. Thickness ranges from 0 to 50 +/- feet. Cheyenne Sandstone Member: Massive, white to buff, fine- to medium-grained sandstone, containing some conglomerate in the lower part, from 0 to 120 +/- feet thick.

Savanna + McAlester + Hartshorne + Atoka Formations (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

TULSA- "Savanna, McAlester, Hartshorne, and Atoka Formations," shale, sandstone, siltstone, limestone, and coal.

Blaylock Sandstone (Early Silurian) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Sandstone, greenish-gray, fine grained, well indurated, alternating with dark-gray to brown phyllites and shales in lower 100 feet; occurs only in Broken Bow Uplift and adjacent area; thickness, 670 to 804 feet, with maximum thickness in Arkansas 1,500 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Raggedy Mountain Gabbro Group (Early Cambrian) at surface, covers < 0.1 % of this area

LAWTON- Gabbro, anorthosite, and diorite; thickness, as much as 10,000 feet (3,000 m).

Oil Creek and Joins Formation (Middle Ordovician) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray to tan, granular, with greenish-gray shale and brown fine- to medium-grained sandstone; thickness, 600 to 1,100 feet, decreasing eastward. (Simpson Group) Occurs in the ARBUCKLE MTNS.

Goddard Shale (Late Mississippian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- 1. Mainly shale, gray, limonitic; thickness, 3,600 feet in Ardmore Basin, 240-450 feet on Lawrence uplift. In places includes "Rod Club" and "Overbrook Sandstones" and "Union Valley Formation-Wapanucka" shale. Occurs in the ARBUCKLE MTNS. 2. Shale, gray, limonitic; estimated thickness, 500 feet, but may be 2,500. Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- Shale, gray to black, with some sandstones and ironstone concretions; thickness, 500 feet or more. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.

Sylvan Shale + Fernvale Limestone and Viola Limestone (Late Ordovician to Middle Ordovician) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- "Sylvan," shale, dark-greenish-gray; thickness, 60 to 325 feet. "Fernvale" and "Viola," limestone, gray, fine- to coarse-grained; thickness, 350 to 900 feet. Occurs in the ARBUCKLE MTNS.

Pawpaw Sandstone and McNutt Limestone (Early Cretaceous) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- "Pawpaw Sandstone," sandstone, yellowish- to reddish-gray, fine-grained, with gray to reddish-purple sandy clay; thickness, 35 feet. "McNutt Limestone" at base, limestone, grayish-brown, arenaceous, with "Rastellum quadriplicatum;" thickness, 2 to 3 feet.

Wetumka Shale (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

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.

Grayson Marl and Bennington Limestone (Early Cretaceous) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- "Grayson Marl," marl, olive-gray, weakly indurated; thickness, about 25 feet. "Bennington Limestone" at base is moderately indurated, medium bedded; thickness, about 10 feet. McALESTER TEXARKANA- "Grayson Marl," olive-gray, weakly indurated; with Texigryphaea roemeri;" thickness, about 25 feet. "Bennington Limestone" at base, limestone, gray to gray-brown, sandy, fossiliferous, overlapped eastward by Woodbine; thickness, 6 to 18 feet.

Torpedo Formation (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

TULSA- Thin-bedded to massive medium-grained sandstone and shale.

Denton Clay (Early Cretaceous) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Clay and shale, blue- to brownish-gray, and marly, fossiliferous limestone with "Texigryphaea washitaensis;" thickness, 45 to 65 feet.

Weno Clay and Soper Limestone (Early Cretaceous) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- "Weno Clay", clay and shale, brownish-gray, with selenite gypsum; interbedded with red- to yellow-brown fine-grained sandstones; thickness, 30 to 53 feet. "Soper Limestone" at base, limestone, gray-brown to red-brown, compact, fossiliferous, with "Rastellum carinatum;" thickness, 1 to 2 feet.

Lenapah Formation (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

TULSA- Limestone and shale. (Map unit only in Nowata County)

Chattanooga + Fernvale + Fite + Tyner + Burgen + Cotter Formations (Late Mississippian to Early Ordovician) at surface, covers < 0.1 % of this area

TULSA- "Chattanooga Formation," shale and minor sandstone. "Fernvale Formation," limestone. "Fite Formation," limestone. "Tyner Formation," shale and dolomite. "Burgen Sandstone," sandstone and minor dolomite and shale. "Cotter Formation," dolomite and minor sandstone.

Hartshorne Sandstone (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Sandstone, gray to white, medium- to coarse-grained with interbedded middle gray shale and "Lower Hartshorne coal;" thickness, 10 to 300 feet. McALESTER TEXARKANA- Sandstone, tan to gray to white, fine- to coarse-grained, micaceous, quartzose, moderately to well-indurated, with some interbedded gray shale; "Lower Hartshorne coal" in middle and "Upper Hartshorne coal" at top; thickness, 100 to 350 feet, increasing eastward.

Limestone Gap (Early Pennsylvanian) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Shale and sandstone, gray to tan, illitic, chloritic, micaceous, quartzose, fine- to coarse-grained, moderately to well-indurated, with some ironstone concretions and many bottom marks; thickness, approximately 1,000 feet, pinching out in subsurface near Ti Valley Fault. Fault. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.

Kindblade Formation (Early Ordovician) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained, gradational eastward into tan fine- to coarse-grained dolomite; some tan to gray sandstone and shale; thickness, 1,875 to 3,000 feet, decreasing eastward. (Arbuckle Group) Individual Fm description not found. Occurs in the ARBUCKLE MTNS.

Bigfork Chert (Middle Ordovician) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray, and dark-gray to black chert; thickness, 575 feet. Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- Chert, dark-gray to black, with interbedded graptolitic black shales and fossiliferous gray to black cherty limestones; contains asphaltite seams; erodes into a mappable escarpment; thickness, 600 to 800 feet. (Same as Viola Limestone in Arbuckle Mountains.) Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Dornick Hills Group (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Series of tan shales with limestones, limestone conglomerate and sandstone. Top of "Otterville Limestone" down to base of "Lake Ardmore Sandstone;" thickness 1,800 feet. Occurs in the ARDMORE BASIN.

Collier Shale (Early Ordovician to Late Cambrian) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Shale and phyllite, dark-gray to black, with much limestone, some granitic and arkosic pebbles, many quartz and orthoclase pegmatities, and some galena and sphalerite; contains Lower Ordovician conodonts; base covered; exposed thickness, 200 feet. Viersen and Cochran's 25-1 Weyerhaeuser well (9-8-70), spudded in upper Collier to total depth of 10,019 feet in Southeast quarter of Northwest quarter of section 25, Township 5 South, Range 23 East, penetrated dark-gray to black phyllites, quartzites, and dolomitic marble without reaching basement (Goldstein, 1975). Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Holly Creek Formation (Early Cretaceous) at surface, covers < 0.1 % of this area

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.

Butterfly Dolomite + Signal Mountain Limestone + Royer Dolomite and Fort Sill Limestone (Late Cambrian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray, fine-grained, gradational eastward into tan to pink fine- to coarse-grained dolomites; thickness, 570 to 1,600 feet, decreasing eastward. (Arbuckle Group) Occurs in the ARBUCKLE MTNS.

Hilltop Formation (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

OKLAHOMA CITY- Mainly shale, grading upward into massive siltstone and fine- grained sandstone; grades northward into "Barnsdall Formation", "Chanute Formation", and "Dewey Limestone". Thickness ranges from 0 to 200 feet. ARDMORE-SHERMAN- Shale, blue-gray to red-brown, with buff siltstones and fine-grained sandstones at top; thickness, about 70 feet.

Coffeyville or Francis Formation (restricted) (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Shale, dark-blue, 20 to 70 feet thick, with "DeNay Limestone," yellow, massive, 2 to 6 feet thick at base, and 20 feet or more of buff fine- to coarse-grained sandstone and chert conglomerate at top. (Upper Franks Conglomerate).

Womble Formation or Womble Shale (Middle Ordovician to Early Ordovician) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- "Womble Shale"- Shale, black to green; thickness, 250 feet, base covered. Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- "Womble Formation"- Sandstone, phyllites, and shales, greenish-gray to dark-gray to black, weathering red-brown; some black to brown cherty limestones occur in upper part; Middle Ordovician graptolites are found in upper part, and Lower Ordovician graptolites in lower part; basal part faulted; estimated thickness, 1,000 feet or more, with maximum thickness in Arkansas 3,500 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Hunton Group (Early Devonian to Early Silurian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Marlstone, shale, and limestone, buff, ranging in age from Early Silurian to Early Devonian; thickness, 100 to 700 feet, with many unconformities Occurs in the ARBUCKLE MTNS.

Dockum Group (Late Triassic) at surface, covers < 0.1 % of this area

CIMARRON- Upper shale unit: Varicolored siltstone or claystone, conglomerate, fine-grained sandstone, and limestone. Lower sandstone unit: Varicolored, fine- to coarse-grained sandstone with some clay and interbedded shale.

Hogshooter Formation (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

TULSA- Limestone and some shale. (Mapped with the Nellie Bly Formation south of Bartlesville).

Wapanucka Formation and Chickachoc Chert (Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray to brown, spicular, granular to oolitic; alternates with gray shale and calcareous sandstone; thickness, 270 to 720 feet. Chert content increases southeastward. Occurs in the OUACHITA MTNS. McALESTER TEXARKANA- Limestone, gray to brown, oolitic to granular, with sponge-spicular chert in middle 50 to 114 feet with overlying and underlying calcareous sandstones and shales; thickness, 600 to 700 feet, pinching out in subsurface near Ti Valley Fault. Occurs in the OUACHITA MTNS, NORTH OF TI VALLEY FAULT.

Delaware Creek Shale (Mississippian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- 1. Shale, dark-gray to black, fissile, calcareous; thickness, 160 to 750 feet, decreasing northward. Occurs in the ARBUCKLE MTNS. 2. Shale, dark-gray to black fissile; thickness 525 feet. Occurs in the OUACHITA MTNS. McALESTER TEXARKANA- Shale, black, laminated, with limestone, siderite, and phosphatic concretions, and with greenish-gray silty glauconitic shale at base; thickness, approximately 500 feet. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.

Savanna and McAlester Formations (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

FORT SMITH- IPsm "Savanna" and "McAlester Formations" (undifferentiated; T. 15 N., Rs. 18, 19 E.), shale and minor sandstones.

Hoxbar Group (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Upper most member of Glenn Fm, consisting of brown limestone, white sandstone, and shale. "Zuckerman Sandstone" (top eroded) down to base of "Confederate Limestone;" thickness, 2,800 feet. Occurs in the ARDMORE BASIN.

Missouri Mountain Shale (Early Silurian) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Shale, greenish-gray to maroon to black; grades into phyllite in Broken Bow Uplift; contains some thin sandstones and gray conglomerates; a fossiliferous limestone occurs in Southeast quarter section 29, Township 4 South, Range 23 East; mapped as SmOp in Potato Hills, where it is included with Polk Creek Shale; thickness, 60 to 110 feet or less. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Carlton Rhyolite Group (Middle Cambrian) at surface, covers < 0.1 % of this area

CLINTON- Rhyolite flows and tuffs; about 4,500 feet thick; one outlier is shown in southern part of mapped area. LAWTON- Rhyolite flows, tuffs, conglomerate beds, and diabase sills; thickness, 4,500 feet (1,370 m).

San Angelo Sandstone (Early Permian) at surface, covers < 0.1 % of this area

LAWTON- "San Angelo Sandstone," Psa, interstratified sandstone, mudstone conglomerate, and shale, as much as 80 feet (24 m) thick.

Colorado Group (Early Cretaceous) at surface, covers < 0.1 % of this area

CIMARRON- includes: Greenhorn Limestone: Gray fossiliferous limestone and calcareous shale. Graneros Shale: Dark-gray shale.

Bluejacket Sandstone (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- "Bluejacket Sandstone," IPbj, sandstone, at base, of Boggy FM, 8 to 12 feet thick, with 2-foot "Secor coal" 50 feet above top of Bluejacket. McALESTER TEXARKANA- Sandstone, tan, fine- to coarse-grained, micaceous, quartzose, moderately to well-indurated; erodes into a mappable escarpment; thickness, 12 to 266 feet, increasing eastward.

Vamoosa + Tallant + Barnsdall Formations (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

TULSA- "Vamoosa Formation," shale, sandstone, siltstone, and thin limestone. "Tallant Formation," shale, sandstone, and thin limestone. "Barnsdall Formation," shale, siltstone, sandstone, and thin limestone.

Crystal Mountain Sandstone (Early Ordovician) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Sandstone, pink to light-gray to dark-gray, fine- to coarse-grained, quartzose, with well-rounded, frosted grains, quartzitic, fractured in many places, with many quartz and orthoclase veins; 14-foot chert- and limestone-pebble conglomerate occurs at base; thickness, 500 feet or more, with maximum thickness in Arkansas 850 feet (called Lower Cool Creek in Arbuckle Mountains and Roubidoux Sandstone in Ozarks). Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Holdenville and Lenapah Formations (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

TULSA- "Holdenville Formation," shale and minor sandstone and limestone. "Lenapah Formation", limestone and shale. (Map unit only in Tulsa County).

Undifferentiated, Mississisippian, Devonian, Silurian, and Ordovician (Late Mississippian to Early Ordovician) at surface, covers < 0.1 % of this area

FORT SMITH- Mississisippian, Devonian, Silurian, and Ordovician Rocks, Undifferentiated Mississippian and Devonian. "Chattanooga Shale," shale. Devonian. "Sallisaw Formation," limestone, sandstone, and chert; and "Frisco Formation," limestone. Silurian. "Quarry Mountain Formation," limestone; "Tenkiller Formation," limestone; and "Blackgum Formation," limestone and dolomite. Ordovician. "Sylvan Shale," shale; "Fernvale Limestone," limestone; "Fite Limestone," limestone; "Tyner Formation," shale, sandstone, dolomite, and limestone; "Burgen Sandstone," sandstone and minor shales and limestones; and "Cotter Dolomite," dolomite.

Morrowan rocks undifferentiated (Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Shale and sandstone, gray to brown, fine- to coarse-grained;estimated thickness, 3,000 feet Occurs in the OUACHITA MNTS.

Belle City Formation or Limestone (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

OKLAHOMA CITY- "Belle City Limestone"-Consists of two fossiliferous limestone units with an intervening fossiliferous shale. Thickness ranges from 12 to 20 feet; present in southern part of area only, where it is below "Hilltop Formation". ARDMORE-SHERMAN- 'Belle City Formation"-Limestone, gray to buff, dense, in 2 beds each 2 to 3 feet thick, with interbedded dark-gray shale, 10 to 20 feet thick.

Alluvium (Holocene) at surface, covers < 0.1 % of this area

Alluvium

Polk Creek Shale (Late Ordovician) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Shale, black; thickness, 175 feet. Occurs in the OUACHITA MNTS. McALESTER TEXARKANA- Shale and phyllite, dark-gray to black, with some chert nodules; contains many graptolites; thickness, 75 to 140 feet. (Same as Sylvan Shale in Arbuckle Mountains.) Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Lower part of Arbuckle Group and Timbered Hills Group (Late Cambrian) at surface, covers < 0.1 % of this area

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."

Upper Holdenville Formation (Middle Pennsylvanian) at surface, covers < 0.1 % of this area

ENID- Mainly shale with interbedded fine-grained sandstone locally containing beds of limestone. Only a few feet is exposed in quadrangle.

Morrowan-Atokan (?) rocks undifferentiated (Middle Pennsylvanian to Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Shale and sandstone, gray to brown, fine- to coarse-grained; thickness, 5,000 to 9,000 feet. Occurs in the OUACHITA MNTS

Missouri Mountain and Polk Creek Shales (Early Silurian to Late Ordovician) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Shale, greenish-gray to maroon to black; grades into phyllite in Broken Bow Uplift; contains some thin sandstones and gray conglomerates; a fossiliferous limestone occurs in Southeast quarter section 29, Township 4 South, Range 23 East; mapped as SmOp in Potato Hills, where it is included with Polk Creek Shale; thickness, 60 to 110 feet or less. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Exeter (Entrada) Sandstone (Late Jurassic) at surface, covers < 0.1 % of this area

CIMARRON- Massive, white to buff, fine- to medium-grained sandstone 0 to 50 +/- feet thick.

Timbered Hills Group (Late Cambrian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- "Honey Creek Limestone," above, is gray, fine grained; grades eastward into dolomite; thickness 90 to 250 feet. "Reagan Sandstone," at base, is brown, coarse grained; thickness, 60 to 450 feet. Occurs in the ARBUCKLE MTNS.

Eagle Ford Formation (Late Cretaceous) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Shale, dark-gray, plastic; thickness, about 50 feet; top eroded.

Mesozoic rocks undifferentiated (Late Cretaceous to Early Triassic) at surface, covers < 0.1 % of this area

TEXAS- Red shale containing thin layers of yellow and gray clay and indistinctly bedded fine-grained buff, red, white, and gray sandstone. May include beds of Cretaceous, Jurassic, and Triassic ages. Their exposed thickness is less than 100 feet.

DeQueen Limestone (Early Cretaceous) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Limestone and marl, blue- to pinkish- to yellowish-gray, locally siliceous, interbedded with varicolored calcareous shales; basal limestone conglomerate in places where unconformable upon Ouachita rocks but absent where conformable on Holly Creek Formation; contains 80 feet of gypsum and anhydrite in subsurface; thickness, 38 feet, lensing out to 1 foot westward but thickening to 190 feet southeastward in subsurface.

Wapanucka Formation (Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained to oolitic. Mapped separately along Lawrence uplift as IPwal, 30 to 75 feet thick with gray shale, IPwas, below, about 160 feet thick. Occurs in the ARBUCKLE MTNS.

Brownstown Marl (Late Cretaceous) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Marl and clay, gray, calcareous, micaceous, sandy and fine-grained sand, with some interbedded chalky limestones; same as upper Austin Chalk of Texas; thickness, about 100 feet.

Colbert Porphyry (Middle Cambrian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Rhyolite porphyry, red-brown, flow-banded; thickness, 7,500 feet. Probably rests on 7,500 feet of metasedimentary and basaltic rocks in geosynclinal province of western Arbuckle Mountains. (525 million years old) Occurs in the ARBUCKLE MTNS.

Nippewalla Group (Late Permian- Custerian to Cimarronian) at surface, covers < 0.1 % of this area

Dog Creek FM- maroon silty shale, siltstone, fine-grained feldspathic sandstone. Blaine FM- (base B) gypsum beds seperated by dolomite and red shale. Flower Pot Shale -(base FL) red gypsiferous shale silty shale and minor sandstone and siltstone. Cedar Hills Sandstone- feldspathic sandstone, siltstone, and silty shale. Salt Plain FM- red flaky, silty shale and some siltstone with thick salt beds at base. Harper Sandstone with Kingman Sandstone member (base K)- red argillaceous siltstone and fine silty sandstone with a few beds of res shale and white sandstone. Stone Coral FM- dolomite, anhydrite, gypsum and salt.

Templeton Member of Woodbine Formation (Late Cretaceous) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- indurated sandstone and shale, about 75 feet thick, erodes to an escarpment; (Woodbine Formation).

Ogallala Formation (Pliocene to Miocene) at surface, covers < 0.1 % of this area

Ogallala Formation

Atoka, Bloyd and Hale Formations Undifferentiated (Middle Pennsylvanian to Early Pennsylvanian) at surface, covers < 0.1 % of this area

FORT SMITH- IPu Undifferentiated. Atoka, Bloyd, and Hale Formations. IPat "Atoka Formation," shale and sandstone, IPbh "Bloyd Formation," shale and limestone; and "Hale Formation," limestone and sandstone.

Kiowa Formation (Early Cretaceous) at surface, covers < 0.1 % of this area

WOODWARD- Gray and yellow shale and limestone, with many "Texigryphaea" shells locally. At base is 5 to 10 feet of greenish-gray sandstone in places. Thickness ranges up to 140 feet with top eroded. CLINTON- Outliers of the "Kiowa Formation," Kk, dark-gray shale with some thin beds of fossiliferous tan limestone, range in thickness from a few feet to about 20 feet. Associated in some places is a 5- to 10-foot, gray to brown, coarse-grained sandstone and conglomerate assigned to the overlying "Dakota Group," Kd, (lower sandstone part).

Mississippian Rocks above Chattanooga Shale Undifferentiated (Mississippian) at surface, covers < 0.1 % of this area

FORT SMITH- Mu- Undifferentiated Mississippian Rocks above Chattanooga Shale. Includes: Pitkin, Fayetteville, Hindsville, Moorefield, Keokuk and Reeds Spring Formations, and St. Joe Group.

Loess (Holocene to Pleistocene) at surface, covers < 0.1 % of this area

eolian silts

Boone Formation (Early Mississippian- Meramecian to Osagean) at surface, covers < 0.1 % of this area

Boone Formation

Blakely Sandstone (Early Ordovician) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Sandstone, gray to brown, fine- to coarse-grained, quartzose, micaceous; grades into beds above, with sharp quartzitic contact below; thickness, 10 to 15 feet, with maximum thickness in Arkansas 400 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Mazarn Shale (Early Ordovician) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Shale and phyllite, dark-gray to black, micaceous; estimated thickness, 1,000 feet, with maximum thickness in Arkansas 3,000 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Sand sheet deposits (Holocene) at surface, covers < 0.1 % of this area

Sand sheet deposits

Union Valley Formation (with sandstone) (Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray, fine- to medium-grained, IPul, 12 to 25 feet thick; with sandstone, IPus, below, fine- to medium-grained, about 150 to 260 feet thick. Occurs in the ARBUCKLE MTNS.

Doe Creek Lentil of Marlow Formation (Early Permian) at surface, covers < 0.1 % of this area

WOODWARD- In Woods and Woodward Counties, the "Doe Creek Lentil" (Pmd) is a coarse-grained calcareous sandstone with algal clumps and invertebrate fossils, ranging up to 70 feet thick from the base of the Marlow to the Relay Creek Bed, cropping out in a narrow band of high hills striking northeast.

Alluvium (Holocene to Pleistocene) at surface, covers < 0.1 % of this area

unconsolidated sand, silt, clay, and gravel

Douglas Group (Late Pennsylvanian- Virgilian) at surface, covers < 0.1 % of this area

Lawrence FM (base LA)- mostly gray shale and sandstone with minor red shale, coal, gray limestone and conglomerate, thickness ranges from 140ft to 250 ft. Stranger FM- five members containing sandstone, shale, and minor limestone, coal and conglomerate ranging from 100 ft. to 180 ft. thickness.

Sycamore and Welden Limestones (Mississippian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, blue-gray to tan, silty, fine-grained; thickness, 2 to 370 feet, decreasing northeastward. Mapped separately in northeastern Arbuckle Mountains and Mannsville anticline; mapped elsewhere with underlying Woodford Shale. Occurs in the ARBUCKLE MTNS.

Ozan Formation (Late Cretaceous) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Marl and clay, light- to dark- to brownish-gray, micaceous, calcareous, sandy, fine-grained sand, with interbedded chalky limestone; glauconitic marl and sand at base; same as lower Taylor Marl of Texas; thickness, about 100 feet.

Verden Sandstone Lentil of Marlow Formation (Early Permian) at surface, covers < 0.1 % of this area

CLINTON- The "Verden Sandstone Lentil," Pmv, is a coarse-grained, calcareous, fossiliferous sandstone (2 to 10 feet thick) that occurs in the middle of the Marlow, about 25 feet below the Relay Creek Bed and 85 to 95 feet above the base. ARDMORE-SHERMAN- "Verden Sandstone Lentil," Pmv, sandstone, 10 feet thick near middle of Marlow Formation.

Marmaton Group (Early Pennsylvanian- Desmoinesian) at surface, covers < 0.1 % of this area

Includes: Lost Branch FM, Memorial Shale, Lenapah Limestone (base LE), Nowata Shale, Altamont Limestone (base PA), Bandera Shale, Pawnee Limestone (base PA), Labette Shale and Fort Scott Limestone.

Wapanucka Formation (Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained to oolitic. Mapped separately along Lawrence uplift as IPwal, 30 to 75 feet thick with gray shale, IPwas, below, about 160 feet thick. Occurs in the ARBUCKLE MTNS.

Blaine Formation (Permian; Guadalupe Series) at surface, covers < 0.1 % of this area

Blaine Formation

Dune sand sheet deposits (Holocene) at surface, covers < 0.1 % of this area

Dune sand sheet deposits

Union Valley Formation (Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray, fine- to medium-grained, IPul, 12 to 25 feet thick; with sandstone, IPus, below, fine- to medium-grained, about 150 to 260 feet thick. Occurs in the ARBUCKLE MTNS.

Dune Sand (Holocene to Pleistocene) at surface, covers < 0.1 % of this area

unconsolidated dune sand

Woodford Shale (Early Mississippian to Late Dovonian) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Shale and chert, black, fissile, with phosphatic nodules and some greenish-gray silty shale; at base is reddish-brown shale; rests on Pine Top Chert in Northeast quarter of section 5 of Township 2 North, Range 15 East; thickness, 67 feet at Pine Top. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.

Kansas City Group (Middle Pennsylvanian- Missourian) at surface, covers < 0.1 % of this area

Includes: Lane Shale,Wyandotte Limestone (base WY), Liberty Memorial Shale, Iola Limestone (base I), Chanute Shale (base CH), Dewey Limestone, Nellie Bly FM, Cherryvale FM, Dennis Limestone (base DN), Galeburg Shale, Mound Valley Limestone, Ladore Shale, Swope Limestone (base SW), Elm Branch Shale, Hertha Limestone.

Alluvium (Pleistocene) at surface, covers < 0.1 % of this area

unconsolidated sand, silt, clay, and gravel

Basalt (Pliocene) at surface, covers < 0.1 % of this area

CIMARRON- Dark, dense to vesicular volcanic rock 50 to 85 +/- feet thick forming cap rock of Black Mesa.

Cherokee Group (Early Pennsylvanian- Desmoinesian) at surface, covers < 0.1 % of this area

Includes: Cabaniss FM (base CA) with Verdigris Limestone Member (base V) and Mineral coal bed (base MC), Krebs FM with Bluejacket Sandstone Member (base BJ) and Warner Sandstone Member (base WR).

Wabaunsee Group (Late Pennsylvanian- Virgilian) at surface, covers < 0.1 % of this area

Includes: Wood Siding FM, Root Shale, Stotler Limestone (base ST), Pillsbury Shale, Zeandale Limestone (base Z), Willard Shale, Emporia Limestone (base E), Auburn Shale, Bern Limestone (base BR), Scranton Shale, Howard Limestone (base H), and Severy Shale.

Viola Limestone and Bromide Formation (Late Ordovician) at surface, covers < 0.1 % of this area

CLINTON- Limestone, limestone and shale interbedded, and sandstone; thickness, about 900 feet; one outlier is shown in southern part of quadrangle. Simpson and lower units are covered. LAWTON- Limestone, interbedded limestone and shale, and sandstone; thickness about 900 feet (270 m), faulted in isolated areas, top eroded, base covered.

Arkansas Novaculite (Late Devonian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Shale, black, cherty, with much novaculite; thickness, 230 to375 feet. Occurs in the OUACHITA MNTS.

Sumner Group (Late Permian - Cimarronian) at surface, covers < 0.1 % of this area

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

Admire Group (Late Pennsylvanian) at surface, covers < 0.1 % of this area

Includes: Grenola Limestone, Roca Shale, Red Eagle Limestone (base RE), Johnson Shale, Foraker Limestone (base FO), Janesville Shale with Five Point Limestone Member (base FP), Falls City Limestone, and Onaga Shale.

Ogallala Fm (Tertiary) at surface, covers < 0.1 % of this area

Loose to well-cemented sand and gravel

Missouri Mountain Shale and Blaylock Sandstone (Early Silurian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- "Missouri Mountain Shale," shale, black to gray-green to red; thickness, 100 feet; underlain by sandstone, several feet thick, correlated as "Blaylock." Occurs in the OUACHITA MNTS.

Eolian deposits (Quaternary) at surface, covers < 0.1 % of this area

Includes dune sand and silt and Peoria Loess

Meramecian and Osagian Series: Warsaw Limestone and Keokuk Limestone (Mississippian- Osagian) at surface, covers < 0.1 % of this area

Warsaw Limestone- semigranular limestone interlaminated with saccharoidal dolomite with large amounts of gray chert; glauconite occurrs in the lower part. Keokuk Limestone- white tripolitic, chert, siliceous limestone, and dolomite

Pitkin Limestone, Fayetteville Shale (including the Wedington Sandstone member), and Batesville Sandstone (including the Hindsville Limestone Member) (Late Mississippian- Chesterian) at surface, covers < 0.1 % of this area

Pitkin Limestone, Fayetteville Shale (including the Wedington Sandstone member), and Batesville Sandstone (including the Hindsville Limestone Member)

Council Grove Group (Early Permian Gearyan) at surface, covers < 0.1 % of this area

Includes: Speiser Shale, Funston Limestone, Blue Rapids Shale, Crouse Limestone (base CS), Easy Creek Shale, Bader Limestone (base BE), Stearns Shale, Beattie Limestone, Eskridge Shale, and Neva Limestone.

Chase Group (Early Permian - Gearyan) at surface, covers < 0.1 % of this area

Nolans Limestone- upper and lower limestone seperated by shale, 40 ft thick. Odell Shale- mostly red and green shale, 40 ft. thick. Winfield Limestone (base WF)- cherty limestone with fossiliferous gray shale, 25 ft. thick. Doyle Shale- two shale members seperated limestone, 70 ft. thick. Barneston Limestone (base BA)- two thick limestone members seperated by thin limestone, 90 ft. thick: with Fort Riley Limestone Member( base FR)- gray to tan massive to thin bedded limestone with minor gray shale, 45 ft thick. Matfeild Shale- two varicolored shale members seperated by limestone, 80 ft. thick. Wreford Limestone- two cherty limestone members seperated shale, 40 ft. thick.

Shawnee Group (Late Pennsylvanian- Virgilian) at surface, covers < 0.1 % of this area

Includes: Topeka Limestone, Calhoun Shale, Deer Creek Limestone (base DC), Tecumseh Shale, Lecompton Limestone (base LC), Kanwaka Shale, Oread Limestone with Plattsmouth Limestone Member (base PL).

Upper part of Arbuckle Group (Early Ordovician) at surface, covers < 0.1 % of this area

LAWTON- Predominantly limestone and dolomite, 4,000 feet (1,200 m) thick, faulted in isolated areas. "Upper part of Arbuckle Group undifferentiated," Oua, faulted in isolated areas north of Lawton.

McAlester Formation (Middle Pennsylvanian- Des Moinesian) at surface, covers < 0.1 % of this area

McAlester Formation

Terrace deposits (Pleistocene and Holocene) at surface, covers < 0.1 % of this area

Terrace deposits

Dakota Sandstone and Purgatoire Fm (Cretaceous) at surface, covers < 0.1 % of this area

Sandstone and shale

Lansing Group (Middle Pennsylvanian- Missourian) at surface, covers < 0.1 % of this area

Stanton Limestone- three limestone and two shales members, ranges from 15 to 130 ft. thick. Vilas Shale- sandy, carbonaceous gray shale with some sandstone and limestone locally, ranges from 5 to 120 ft. thick. Plattsburg Limestone- two limestone members seperated by shale, ranging from 25 to 115 ft. thick.

Whitehorse Group, undivided (Permian; Guadalupe Series) at surface, covers < 0.1 % of this area

Whitehorse Group, undivided

Unknown (Age uncertain) at surface, covers < 0.1 % of this area

Unknown

Atoka Formation - Lower part (Middle Pennsylvanian- Atokan) at surface, covers < 0.1 % of this area

Atoka Formation - Lower part

Quartermaster Formation and Whitehorse Group, undivided (Permian; Guadalupe Series) at surface, covers < 0.1 % of this area

Quartermaster Formation and Whitehorse Group, undivided

Quaternary deposit, undivided (Quaternary) at surface, covers < 0.1 % of this area

Quaternary deposit, undivided

Kiowa Shale and Cheyenne Sandstone (Early Cretaceous) at surface, covers < 0.1 % of this area

Kiowa Shale or FM- light -gray to black illitic shale with thin coquinoidal limestone beds at the base; sandstone lenses common. Cheyenne Sandstone- massive to crossbedded, light-gray to buff fine-grained sandstone with lenses of gray sandy shale and conglomerate.

Wapanucka Formation (Early Pennsylvanian) at surface, covers < 0.1 % of this area

ARDMORE-SHERMAN- Limestone, gray to tan, fine-grained to oolitic. Mapped separately along Lawrence uplift as IPwal, 30 to 75 feet thick with gray shale, IPwas, below, about 160 feet thick. Occurs in the ARBUCKLE MTNS.

Atoka Formation - Upper part (Middle Pennsylvanian- Atokan) at surface, covers < 0.1 % of this area

Atoka Formation - Upper part

Dakota Group (Early Cretaceous) at surface, covers < 0.1 % of this area

CLINTON- Outliers of the "Kiowa Formation," Kk, dark-gray shale with some thin beds of fossiliferous tan limestone, range in thickness from a few feet to about 20 feet. Associated in some places is a 5- to 10-foot, gray to brown, coarse-grained sandstone and conglomerate assigned to the overlying "Dakota Group," Kd, (lower sandstone part).

Atoka Formation - Middle part (Middle Pennsylvanian- Atokan) at surface, covers < 0.1 % of this area

Atoka Formation - Middle part

Pine Top Chert (Early Devonian) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Limestone, chert, and cherty limestone, gray to light-gray to tan to white and pink; contains Haragan brachiopods; at top is an 8-foot chert conglomerate; base not exposed; thickness, 60 feet. Occurs in the OUACHITA MTNS NORTH OF TI VALLEY FAULT.

Diorite Sill (Late Ordovician ?) at surface, covers < 0.1 % of this area

McALESTER TEXARKANA- Diorite, light-greenish-gray, medium- to fine-grained, quartz-free, with much andesine plagioclase and ferromagnesian minerals altered to chlorite and limonite; occurs in sections 10 and 15, Township 5 South, Range 23 East, in Womble Formation, striking North, 45 degrees East and dipping 10 degrees to 20 degrees Northwest; thickness, 2 to 10 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.

Alluvium (Holocene) at surface, covers < 0.1 % of this area

Alluvial deposits of present streams

Savanna Formation (Late Pennsylvanian- Des Moinesian) at surface, covers < 0.1 % of this area

Savanna Formation

Guadalupia Series: Big Basin Formation, Day Creek Dolomite, and Whitehorse Formation (Late Permian- Custerian to Cimarronian) at surface, covers < 0.1 % of this area

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.

Fort Worth Limestone and Duck Creek Formation, undivided (Early Cretaceous) at surface, covers < 0.1 % of this area

Fort Worth Limestone and Duck Creek Formation, undivided

Petrolia Formation (Permian; Wolfcamp to Leonard Series) at surface, covers < 0.1 % of this area

Petrolia Formation

Arbuckle Group and Timbered Hills Group (Late Cambrian) at surface, covers < 0.1 % of this area

CLINTON- Limestone and dolomite; one outlier at southern end of quadrangle, about 1,200 feet thick.

Stanley Shale (Early Mississippian) at surface, covers < 0.1 % of this area

Stanley Shale - Includes Chickasaw Creek Chert equivalent of Harlton (1938) near top and Hatton Tuff Lentil and Hot Springs Sandstone Member near base

Antlers Sand (Early Cretaceous) at surface, covers < 0.1 % of this area

Antlers Sand

Spavinaw Granite (Middle Proterozoic) at surface, covers < 0.1 % of this area

TULSA- no description given.

Harthshorne Sandstone (Middle Pennsylvanian- Des Moinesian) at surface, covers < 0.1 % of this area

Harthshorne Sandstone

Dockum Group (Triassic) at surface, covers < 0.1 % of this area

Red sandstone, siltstone, and local limestone

Clear Fork Group (Permian; Leonard Series) at surface, covers < 0.1 % of this area

Clear Fork Group

Morrison, Ralston Creek, and Entrada (or Exeter) Fms (Jurassic) at surface, covers < 0.1 % of this area

Morrison, Ralston Creek, and Entrada (or Exeter) Fms

Jackfork Sandstone (Early Pennsylvanian- Morrowan) at surface, covers < 0.1 % of this area

Jackfork Sandstone

Blackwater Draw Formation (Pleistocene) at surface, covers < 0.1 % of this area

Blackwater Draw Formation

Kiamichi Formation (Early Cretaceous; Comanchean Series) at surface, covers < 0.1 % of this area

Kiamichi Formation

Eagle Ford Formation (Late Cretaceous) at surface, covers < 0.1 % of this area

Eagle Ford Formation

Cane Hill Member of Hale Formation (Early Pennsylvanian- Morrowan) at surface, covers < 0.1 % of this area

Cane Hill Member of Hale Formation