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Geologic units in Texas (state in United States)

Additional scientific data in this geographic area

alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 7 % of this area

alluvium

Lithology: sand; silt; clay or mud; gravel

Blackwater Draw Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 5 % of this area

Blackwater Draw Formation

Lithology: sand; silt; clay or mud

sand sheet deposits (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 5 % of this area

sand sheet deposits

Lithology: sand; silt

Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 4 % of this area

Terrace deposits

Quaternary deposit, undivided (Phanerozoic | Cenozoic | Quaternary) at surface, covers 3 % of this area

sand, silt, clay, and gravel. locally indurated with calcium carbonate (caliche); includes point bar, natural levee, stream channel, sand dune, terrace, alluvial fan, landslide bolson and playa deposits

Lissie Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle) at surface, covers 2 % of this area

Lissie Formation

Lithology: sand; silt; clay or mud

Beaumont Formation, areas predominantly clay (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late) at surface, covers 2 % of this area

Beaumont Formation, areas predominantly clay

Lithology: clay or mud; silt

Yegua Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Middle) at surface, covers 2 % of this area

Yegua Formation

Queen City Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 2 % of this area

Queen City Sand

Beaumont Formation, areas predominantly sand (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Late) at surface, covers 2 % of this area

Beaumont Formation, areas predominantly sand

Lithology: sand; silt; clay or mud; gravel

Ogallala Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene Miocene) at surface, covers 2 % of this area

Ogallala Formation

older alluvial deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 2 % of this area

older alluvial deposits

Lithology: gravel; sand; silt

Wilcox Group, undivided (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers 2 % of this area

Wilcox Group, undivided

alluvial fan deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 2 % of this area

alluvial fan deposits

Lithology: alluvial fan

Goliad Formation (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 2 % of this area

Goliad Formation

Austin Chalk (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 1 % of this area

Austin Chalk

Willis Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene) at surface, covers 1 % of this area

Willis Formation

Lithology: clay or mud; silt; sand; gravel

Clear Fork Group (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 1 % of this area

Clear Fork Group

Fleming Formation (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 1 % of this area

Fleming Formation

Lithology: clay or mud; sandstone

dune sand sheet deposits (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 1 % of this area

dune sand sheet deposits

Lithology: sand; silt

Sparta Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 1 % of this area

Sparta Sand

Cook Mountain Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 1 % of this area

Cook Mountain Formation

Lithology: clay or mud; sandstone; coal

Leona Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 0.9 % of this area

Leona Formation

Lithology: sand; gravel; clay or mud

Carizzo Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.9 % of this area

Carizzo Sand

Lithology: sandstone

Reklaw Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.9 % of this area

Reklaw Formation

Lithology: sandstone; clay or mud

Jackson Group, undivided (Phanerozoic | Cenozoic | Tertiary | Eocene Oligocene) at surface, covers 0.9 % of this area

Jackson Group, undivided

Devils River Limestone (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers 0.9 % of this area

Devils River Limestone

Edwards Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.8 % of this area

Edwards Limestone

Blaine Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.8 % of this area

Blaine Formation

Ozan Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.8 % of this area

Ozan Formation

Lithology: clay or mud

Laredo Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Middle) at surface, covers 0.8 % of this area

Laredo Formation

Lithology: sandstone; clay or mud

Catahoula Formation (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.7 % of this area

Catahoula Formation

Bouquillas Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 0.7 % of this area

Bouquillas Formation

Lingos Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle(?) Pleistocene-Late(?) Holocene) at surface, covers 0.7 % of this area

Lingos Formation

Lithology: sand; gravel; clay or mud; silt

Eagle Ford Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 0.7 % of this area

Eagle Ford Formation

Lithology: shale; siltstone; limestone

Uvalde Gravel (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene) at surface, covers 0.7 % of this area

Uvalde Gravel

Lithology: gravel; chert

Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.7 % of this area

Woodbine Formation

Weches Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.7 % of this area

Weches Formation

Lithology: sand; clay or mud

Santa Elena Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.6 % of this area

Santa Elena Limestone

Lithology: limestone; mudstone; chert

sand deposits, undivided (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 0.6 % of this area

sand deposits, undivided

Lithology: sand; silt

Midway Group, undivided (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 0.6 % of this area

Midway Group, undivided

El Pico Clay (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.6 % of this area

El Pico Clay

Lithology: clay or mud; sandstone; coal

Whitehorse Group, undivided (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.6 % of this area

Whitehorse Group, undivided

Lithology: sandstone; shale; evaporite

Buda Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.6 % of this area

Buda Limestone

Lithology: limestone

Calvert Bluff Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers 0.5 % of this area

Calvert Bluff Formation

Lithology: mudstone; sandstone; coal

Oakville Sandstone (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 0.5 % of this area

Oakville Sandstone

Lithology: sandstone; clay or mud

Glen Rose Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.5 % of this area

Glen Rose Limestone

Manning Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.5 % of this area

Manning Formation

Wills Point Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 0.5 % of this area

Wills Point Formation

Lithology: clay or mud; limestone

Seymour Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle [Irvingtonian]) at surface, covers 0.5 % of this area

Seymour Formation

Lithology: sand; gravel; clay or mud

Salado and Castile Formations, undivided (Phanerozoic | Paleozoic | Permian [Ochoa]) at surface, covers 0.5 % of this area

Salado and Castile Formations, undivided

Wolfe City Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.4 % of this area

Wolfe City Formation

Lithology: sand; silt; mudstone

caliche deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.4 % of this area

caliche deposits

Lithology: evaporite

Whitsett Formation (Phanerozoic | Cenozoic | Tertiary | Eocene Oligocene) at surface, covers 0.4 % of this area

Whitsett Formation

Markley Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian) at surface, covers 0.4 % of this area

Markley Formation

Antlers Sand (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.4 % of this area

Antlers Sand

Quaternary-Tertiary bolson deposits (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene) at surface, covers 0.4 % of this area

Quaternary-Tertiary bolson deposits

Deweyville Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene (?)) at surface, covers 0.4 % of this area

Deweyville Formation

Lithology: sand; silt; clay or mud

Buda Limestone and Del Rio Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 0.4 % of this area

Buda Limestone and Del Rio Clay, undivided

Washita Group (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean] Cretaceous-Late ) at surface, covers 0.4 % of this area

Washita Group

Lithology: clay or mud; limestone

Hensell Sand (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean) at surface, covers 0.4 % of this area

Hensell Sand

Cadell Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.4 % of this area

Cadell Formation

Bigford Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.4 % of this area

Bigford Formation

high gravel deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 0.4 % of this area

high gravel deposits

Lithology: gravel; silt; sand

bolson deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.3 % of this area

bolson deposits

Fort Worth Limestone and Duck Creek Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.3 % of this area

Fort Worth Limestone and Duck Creek Formation, undivided

Paluxy Sand and Glen Rose Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.3 % of this area

Paluxy Sand and Glen Rose Limestone, undivided

Pecan Gap Chalk (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.3 % of this area

Pecan Gap Chalk

Quartermaster Formation and Whitehorse Group, undivided (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.3 % of this area

Quartermaster Formation and Whitehorse Group, undivided

Neylandville and Marlbrook Marls, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.3 % of this area

Neylandville and Marlbrook Marls, undivided

Lithology: clay or mud

Petrolia Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp Leonard]) at surface, covers 0.3 % of this area

Petrolia Formation

Fredericksburg Group (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers 0.3 % of this area

Fredericksburg Group

Archer City Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers 0.3 % of this area

Archer City Formation

Grayson Marl and Main Street Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Late) at surface, covers 0.3 % of this area

Grayson Marl and Main Street Limestone, undivided

Lithology: mudstone; limestone

Nocona Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp Leonard]) at surface, covers 0.3 % of this area

Nocona Formation

Hueco Limestone (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers 0.3 % of this area

Hueco Limestone

silt sheet (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 0.3 % of this area

silt sheet

Lithology: silt; sand

Escondido Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.3 % of this area

Escondido Formation

Lithology: shale; siltstone; sandstone

Kincaid Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 0.3 % of this area

Kincaid Formation

Lithology: sand; clay or mud; limestone

Navarro Group and Marlbrook Marl, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.3 % of this area

Navarro Group and Marlbrook Marl, undivided

Bofecillos volcano volcanic rocks, including units 1-8 of Rawls Formation and lava flows in upper part of Fresno Formation (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.3 % of this area

Bofecillos volcano volcanic rocks, including units 1-8 of Rawls Formation and lava flows in upper part of Fresno Formation

Town Mountain Granite (preCambrian-Proterozoic) at surface, covers 0.3 % of this area

Town Mountain Granite

Lithology: granite; porphyry

Waggoner Ranch Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.3 % of this area

Waggoner Ranch Formation

Victorio Peak Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.2 % of this area

Victorio Peak Formation

Duff Formation (with Decie Member from Paisano caldera shown separately), Cottonwood Springs Basalt, Potato Hill Andesite, Sheep Canyon Basalt, Crossen Trachyte, and Pruett Formation, undivided (Phanerozoic | Cenozoic | Tertiary | Eocene-Late Oligocene-Early) at surface, covers 0.2 % of this area

Duff Formation (with Decie Member from Paisano caldera shown separaetly), Cottonwood Springs Basalt, Potato Hill Andesite, Sheep Canyon Basalt, Crossen Trachyte, and Pruett Formation, undivided

Marlbrook Marl (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.2 % of this area

Marlbrook Marl

Lithology: clay or mud; limestone

barrier island deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.2 % of this area

barrier island deposits

Lithology: sand; silt

Walnut Clay (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

Walnut Clay

Trujillo Formation (Phanerozoic | Mesozoic | Triassic-Late) at surface, covers 0.2 % of this area

Trujillo Formation

Tanyard Formation (Phanerozoic | Paleozoic | Ordovician-Early) at surface, covers 0.2 % of this area

Tanyard Formation

Lueders Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.2 % of this area

Lueders Formation

Lithology: shale; limestone

Thrifty and Graham Formations, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Virgil]) at surface, covers 0.2 % of this area

Thrifty and Graham Formations, undivided

Pawpaw Formation, Weno Limestone, and Denton Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

Pawpaw Formation, Weno Limestone, and Denton Clay, undivided

Finlay Limestone (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean Albian]) at surface, covers 0.2 % of this area

Finlay Limestone

Hooper Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 0.2 % of this area

Hooper Formation

Lithology: mudstone; sandstone

Admiral Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers 0.2 % of this area

Admiral Formation

Harpersville Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Virgil]) at surface, covers 0.2 % of this area

Harpersville Formation

Chinati Mountains caldera volcanic rocks, including Chinati Mountains Group, Mitchell Mesa Ignimbrite, and type area of Petan Basalt (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.2 % of this area

Chinati Mountains caldera volcanic rocks, including Chinati Mountains Group, Mitchell Mesa Ignimbrite, and type area of Petan Basalt

Simsboro Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 0.2 % of this area

Simsboro Formation

Lithology: sand; mudstone

playa deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.2 % of this area

playa deposits

Lithology: clay or mud; silt

undivided part Fredericksberg Group (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

undivided part Fredericksberg Group

Tecovas Formation (Phanerozoic | Mesozoic | Triassic-Late) at surface, covers 0.2 % of this area

Tecovas Formation

Bell Canyon Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.2 % of this area

Bell Canyon Formation

Lithology: sandstone; limestone

Gober Chalk and Roxton Limestone (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.2 % of this area

Gober Chalk and Roxton Limestone

Lithology: limestone; limestone

Travis Peak Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

Travis Peak Formation

Grape Creek Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.2 % of this area

Grape Creek Formation

Lithology: shale; limestone

Indio Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers 0.2 % of this area

Indio Formation

Talpa Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.2 % of this area

Talpa Formation

Lithology: shale; limestone

Tahoka Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Wisconsinan]) at surface, covers 0.2 % of this area

Tahoka Formation

Lithology: clay or mud; silt; sand; gravel

Rustler Formation (Phanerozoic | Paleozoic | Permian [Ochoa]) at surface, covers 0.2 % of this area

Rustler Formation

Cherry Canyon Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.2 % of this area

Cherry Canyon Formation

Wellborn Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.2 % of this area

Wellborn Formation

Twin Mountains Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

Twin Mountains Formation

Nacatoch Sand (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.2 % of this area

Nacatoch Sand

Lithology: clay or mud; sand; sandstone

younger volcanic rocks of Davis Mountains area including Brooks Mountain, Goat Canyon, Medley, Barrel Springs, Wild Cherry, Eppenaurer Ranch, Mount Locke, and Merrill Formations (Phanerozoic | Cenozoic | Tertiary | Oligocene-Early) at surface, covers 0.2 % of this area

younger volcanic rocks of Davis Mountains area including Brooks Mountain, Goat Canyon, Medley, Barrel Springs, Wild Cherry, Eppenaurer Ranch, Mount Locke, and Merrill Formations

Lithology: trachyte; rhyolite; tuff; latite

Paluxy Sand (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

Paluxy Sand

Lithology: sand; sandstone; limestone

Hickory Sandstone Member (Phanerozoic | Paleozoic | Cambrian-Middle) at surface, covers 0.2 % of this area

Hickory Sandstone Member

Gorman Formation (Phanerozoic | Paleozoic| Ordovician-Early) at surface, covers 0.2 % of this area

Gorman Formation

Jagger Bend and Valera Formations, undivided (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.2 % of this area

Jagger Bend and Valera Formations, undivided

Lithology: shale; mudstone; limestone

Alluvium in Rio Grande, subdivided into areas predominantly of clay (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 0.2 % of this area

Alluvium in Rio Grande, subdivided into areas predominantly of clay

Lithology: silt; clay or mud

Quartermaster Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.2 % of this area

Quartermaster Formation

Valley Spring Gneiss (preCambrian-Proterozoic) at surface, covers 0.2 % of this area

Valley Spring Gneiss

Tesnus Formation (Phanerozoic | Paleozoic | Carboniferous Mississippian-Late Pennsylvanian-Early) at surface, covers 0.2 % of this area

Tesnus Formation

Bead Mountain Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.2 % of this area

Bead Mountain Formation

Lithology: shale; limestone

Vieja Group, including Bracks Rhyolite, Chambers and Colmena Tuffs and Gill Breccia (Phanerozoic | Cenozoic | Tertiary | Eocene Oligocene) at surface, covers 0.2 % of this area

Vieja Group, including Bracks Rhyolite, Chambers and Colmena Tuffs and Gill Breccia

undivided parts of Washita and Fredericksberg Groups (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

undivided parts of Washita and Fredericksberg Groups

Oligocene intrusive rocks (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.2 % of this area

Oligocene intrusive rocks

Packsaddle Schist (preCambrian-Proterozoic [Llano]) at surface, covers 0.2 % of this area

Packsaddle Schist

Cox Sandstone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

Cox Sandstone

Ranger Limestone and Placid Creek Shale, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers 0.2 % of this area

Ranger Limestone and Placid Creek Shale, undivided

Lithology: shale; limestone

San Angelo Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.2 % of this area

San Angelo Formation

Home Creek Limestone and Colony Creek Shale, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers 0.1 % of this area

Home Creek Limestone and Colony Creek Shale, undivided

Lithology: shale; limestone; sandstone

Bonham Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.1 % of this area

Bonham Formation

Lithology: mudstone; clay or mud

Palo Pinto Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers 0.1 % of this area

Palo Pinto Formation

Lithology: sandstone; shale; limestone

Elm Creek Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers 0.1 % of this area

Elm Creek Formation

Lithology: shale; mudstone; limestone

Maxon Sandstone and Glen Rose Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.1 % of this area

Maxon Sandstone and Glen Rose Limestone, undivided

Lithology: sandstone; limestone

Mineral Wells Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers 0.1 % of this area

Mineral Wells Formation

Salmon Peak Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.1 % of this area

Salmon Peak Limestone

Lithology: limestone; mudstone; chert

Quaternary-Tertiary deposits, undivided (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene) at surface, covers 0.1 % of this area

Quaternary-Tertiary deposits, undivided

Lithology: gravel; conglomerate

Aguja Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 0.1 % of this area

Aguja Formation

Lithology: clay or mud; sandstone; coal

Navarro Group, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.1 % of this area

Navarro Group, undivided

Lithology: clay or mud; sand; sandstone

Frio Clay (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.1 % of this area

Frio Clay

Lithology: clay or mud

Chisos Formation of Schiebout et al (1987) and the Big Yellow Sandstone Member of their Tornillo Formation, undivided (Phanerozoic | Cenozoic | Tertiary | Eocene Oligocene) at surface, covers 0.1 % of this area

Chisos Formation of Schiebout et al (1987) and the Big Yellow Sandstone Member of their Tornillo Formation, undivided

Santa Anna Branch Shale and Sedwick and Moran Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers 0.1 % of this area

Santa Anna Branch Shale and Sedwick and Moran Formations, undivided

Riley Formation showing Lion Mountain Sandstone and Cap Mountain Limestone Members, undivided (Phanerozoic | Paleozoic | Cambrian-Middle) at surface, covers 0.1 % of this area

Riley Formation showing Lion Mountain Sandstone and Cap Mountain Limestone Members, undivided

Wilberns Formation showing Point Peak, Morgan Creek Limestone, and Welge Sandstone Members, undivided (Phanerozoic | Paleozoic | Cambrian-Furongian) at surface, covers 0.1 % of this area

Wilberns Formation showing Point Peak, Morgan Creek Limestone, and Welge Sandstone Members, undivided

Goodland Limestone and Walnut Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers 0.1 % of this area

Goodland Limestone and Walnut Clay, undivided

Lithology: limestone; clay or mud

Marble Falls Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Morrow]) at surface, covers 0.1 % of this area

Marble Falls Limestone

Lithology: limestone; shale

land slide deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 0.1 % of this area

land slide deposits

Lithology: landslide

Blossom Sand (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.1 % of this area

Blossom Sand

Lithology: sand; clay or mud

Capitan Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers 0.1 % of this area

Capitan Formation

Anacacho Limestone (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.1 % of this area

Anacacho Limestone

Lithology: limestone; mudstone

barrier ridge and barrier flat deposts (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 0.1 % of this area

barrier ridge and barrier flat deposts

Lithology: sand; silt; clay or mud

Dockum Group, undivided (Phanerozoic | Mesozoic | Triassic-Late) at surface, covers 0.1 % of this area

Dockum Group

Wilberns Formation showing San Saba Member (Phanerozoic | Paleozoic | Cambrian-Furongian) at surface, covers 0.1 % of this area

Wilberns Formation showing San Saba Member

Infiernito caldera volcanic rocks including Capote Mountain Tuff, Tsh2 of Shely Group, Buckshot Ignimbrite, and Tm1 of Morita Ranch Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Late) at surface, covers 0.1 % of this area

Infiernito caldera volcanic rocks including Capote Mountain Tuff, Tsh2 of Shely Group, Buckshot Ignimbrite, and Tm1 of Morita Ranch Formation

Manning, Wellborn, and Cadell Formations, undivided (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 0.1 % of this area

Manning, Wellborn, and Cadell Formations, undivided

Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.1 % of this area

Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided

Lithology: limestone; shale

Brazos River Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines]) at surface, covers 0.1 % of this area

Brazos River Formation

Lithology: sandstone; conglomerate

Catahoula Formation and Frio Clay, undivided (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.1 % of this area

Catahoula Formation and Frio Clay, undivided

Pueblo Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers 0.1 % of this area

Pueblo Formation

Lithology: mudstone; sandstone

Winchell Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers 0.1 % of this area

Winchell Limestone

Lithology: limestone; shale

Neylandville Marl (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Neylandville Marl

Lithology: clay or mud

Strawn Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atoka Des Moines]) at surface, covers < 0.1 % of this area

Strawn Group

Brownstown Marl (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Brownstown Marl

Lithology: clay or mud

lower part of Washita Group (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

lower part of Washita Group

Lithology: limestone; mudstone

Kemp clay (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Kemp clay

Lithology: clay or mud; sandstone

Navarro and Taylor Groups, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Navarro and Taylor Groups, undivided

sand dune deposits (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

sand dune deposits

Lithology: sand; silt

in Rio Grande delta area, clay veneer over meanderbelt sand (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

in Rio Grande delta area, clay veneer over meanderbelt sand

Lithology: clay or mud; sand

Coleman Junction Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Coleman Junction Formation

Alluvium in Rio Grande, subdivided into areas predominantly of sand (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

Alluvium in Rio Grande, subdivided into areas predominantly of sand

Lithology: sand; silt

Jones Basalt (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

Jones Basalt

Lithology: basalt; trachyandesite

Kiamichi Formation (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

Kiamichi Formation

Grindstone Creek Formation, expanded (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines]) at surface, covers < 0.1 % of this area

Grindstone Creek Formation, expanded

Lithology: shale; sandstone; limestone

Pawpaw Formation and upper limestone unit of Weno Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Pawpaw Formation and upper limestone unit of Weno Formation, undivided

Lithology: mudstone; limestone

Fleming Formation and Oakville Sandstone, undivided (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers < 0.1 % of this area

Fleming Formation and Oakville Sandstone, undivided

Lithology: clay or mud; sandstone

Moran Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Moran Formation

Santa Anna Branch Shale (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Santa Anna Branch Shale

Pen Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Pen Formation

Lithology: clay or mud; sandstone

McKnight Formation (Phanerozoic | Mesozoic | Cretaceous-Early ) at surface, covers < 0.1 % of this area

McKnight Formation

Lithology: limestone; shale; chert

Wolf Mountain Shale (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers < 0.1 % of this area

Wolf Mountain Shale

Lithology: shale; sandstone; limestone

Campagrande Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Campagrande Formation

Eocene intrusive rocks (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Eocene intrusive rocks

Eagle Ford Formation and Woodbine Formations, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Eagle Ford Formation and Woodbine Formations, undivided

Perdiz Conglomerate, Tascotal Formation, and tuffaceous sediments of Fresno Formation (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

Perdiz Conglomerate, Tascotal Formation, and tuffaceous sediments of Fresno Formation

Kemp clay and Corsicana Marl, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Kemp clay and Corsicana Marl, undivided

Lithology: clay or mud; sandstone

Brushy Canyon Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Brushy Canyon Formation

Younger granitic intrusion (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Younger granitic intrusion

Lithology: granite; aplite; pegmatite

pond deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers < 0.1 % of this area

pond deposits

Lithology: silt; sand

Javelina Member of Tornillo Formation (Phanerozoic | Mesozoic Cenozoic | Cretaceous-Late Tertiary | Paleocene) at surface, covers < 0.1 % of this area

Javelina Member of Tornillo Formation

Lithology: clay or mud; sandstone

Honeycut Formation (Phanerozoic | Paleozoic | Ordovician-Early) at surface, covers < 0.1 % of this area

Honeycut Formation

Wilke Ranch Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers < 0.1 % of this area

Wilke Ranch Formation

Mingus Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines]) at surface, covers < 0.1 % of this area

Mingus Formation

Lithology: shale; sandstone; limestone; coal

fill and spoil (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

fill and spoil

Lithology: sand; silt; clay or mud

Woods Hollow Shale, Fort Pena Formation, Alsate Shale, Marathon Limestone, and Dagger Flat Sandstone, undivided (Phanerozoic | Paleozoic| Cambrian Ordovician) at surface, covers < 0.1 % of this area

Woods Hollow Shale, Fort Pena Formation, Alsate Shale, Marathon Limestone, and Dagger Flat Sandstone, undivided

clay dune (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

clay dune

Lithology: sand; silt; clay or mud

Smithwick Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atoka]) at surface, covers < 0.1 % of this area

Smithwick Formation

Yazoo Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Late) at surface, covers < 0.1 % of this area

Yazoo Formation

Lithology: clay or mud

Tertiary intrusive rocks, undivided (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Tertiary intrusive rocks, undivided

Lithology: granite; granite

Yucca Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Yucca Formation

Sedwick Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Sedwick Formation

Deweyville Formation with higher level? (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene (?)) at surface, covers < 0.1 % of this area

Deweyville Formation with higher level?

Lithology: clay or mud; silt

Olmos Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Olmos Formation

Lithology: clay or mud; sandstone; coal

Fredericksberg Group and Maxon Sandstone, undivided (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

Fredericksberg Group and Maxon Sandstone, undivided

older volcanic rocks of Davis and Barilla Mountains, including Sheep Pasture, Sleeping Lion, Frazier Canyon, Adobe Canyon, and Limpia formations, Gomez Tuff, Star Mountain Rhyolite, and Huelster Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Late) at surface, covers < 0.1 % of this area

older volcanic rocks of Davis and Barilla Mountains, including Sheep Pasture, Sleeping Lion, Frazier Canyon, Adobe Canyon, and Limpia formations, Gomez Tuff, Star Mountain Rhyolite, and Huelster Formation

El Picacho Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

El Picacho Formation

Lithology: claystone; sandstone; coal

Wiley Mountain caldera volcanic rocks (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Wiley Mountain caldera volcanic rocks

Barnett Formation, Chappel Limestone, Houy, Zesch, Bear Spring, and Stribling Formations, and Pillar Bluff Limestone, undivided (Phanerozoic | Paleozoic | Devonian Carboniferous Mississippian-Early Mississippian-Middle Mississippian-Late) at surface, covers < 0.1 % of this area

Barnett Formation, Chappel Limestone, Houy, Zesch, Bear Spring, and Stribling Formations, and Pillar Bluff Limestone, undivided

gypsum of Rustler, Salado, and Castile Formations, undivided (Phanerozoic | Paleozoic | Permian [Ochoa]) at surface, covers < 0.1 % of this area

gypsum of Rustler, Salado, and Castile Formations, undivided

Lithology: evaporite

Bluff Mesa Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Bluff Mesa Formation

Lithology: limestone; sandstone; shale

Ojinaga Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Ojinaga Formation

Lithology: shale; sandstone; limestone

Magdalena Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian (?)) at surface, covers < 0.1 % of this area

Magdalena Formation

Lithology: limestone; shale

Chinle Formation (Phanerozoic | Mesozoic | Triassic-Late) at surface, covers < 0.1 % of this area

Chinle Formation

Santa Elena Limestone, Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Santa Elena Limestone, Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided

Lithology: limestone; shale

Gatuna Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Middle(?)) at surface, covers < 0.1 % of this area

Gatuna Formation

Eagle Mountains caldera volcanic rocks (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

Eagle Mountains caldera volcanic rocks

Del Rio Clay (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Del Rio Clay

Lithology: mudstone; limestone

San Miguel Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

San Miguel Formation

Cedarton Shale and Adams Branch Limestone, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers < 0.1 % of this area

Cedarton Shale and Adams Branch Limestone, undivided

Lithology: shale; sandstone; limestone

Washita and Fredericksburg Groups, undivided (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

Washita and Fredericksburg Groups, undivided

Boracho Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Boracho Limestone

Lithology: limestone

alkali flat deposits (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

alkali flat deposits

Hazel Formation (preCambrian-Proterozoic [Grenville]) at surface, covers < 0.1 % of this area

Hazel Formation

Skinner Ranch and Hess Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Skinner Ranch and Hess Formations, undivided

Georgetown Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Georgetown Limestone

Lithology: limestone; mudstone

undivided part of Washita Group (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

undivided part of Washita Group

bolson deposits (Phanerozoic | Cenozoic | Tertiary | Pliocene) at surface, covers < 0.1 % of this area

bolson deposits

Cutoff Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers < 0.1 % of this area

Cutoff Formation

Jasper Creek Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missouri]) at surface, covers < 0.1 % of this area

Jasper Creek Formation

West Nueces Formation (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

West Nueces Formation

Lithology: limestone

Caballos Novaculite and Maravillas Chert, undivided (Phanerozoic | Paleozoic | Ordovician-Late Devonian Carboniferous Mississippian) at surface, covers < 0.1 % of this area

Caballos Novaculite and Maravillas Chert, undivided

Whitehorse Group and Blaine Formation, undivided (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Whitehorse Group and Blaine Formation, undivided

Del Rio Clay and Georgetown Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian] ) at surface, covers < 0.1 % of this area

Del Rio Clay and Georgetown Limestone, undivided

Lithology: clay or mud; limestone

Annona Chalk (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Annona Chalk

Lithology: limestone

El Paso Formation and Bliss Sandstone, undivided (Phanerozoic | Paleozoic| Cambrian-Furongian(?) Ordovician-Early) at surface, covers < 0.1 % of this area

El Paso Formation and Bliss Sandstone, undivided

Dimple Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early) at surface, covers < 0.1 % of this area

Dimple Formation

Lithology: limestone; shale

Bone Spring Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers < 0.1 % of this area

Bone Spring Formation

Haymond Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early) at surface, covers < 0.1 % of this area

Haymond Formation

Lazy Bend Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines]) at surface, covers < 0.1 % of this area

Lazy Bend Formation

Lithology: shale; sandstone; limestone

Rita Blanca Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene) at surface, covers < 0.1 % of this area

Rita Blanca Formation

Lithology: sand; clay or mud; sandstone

Tessey Limestone (Phanerozoic | Paleozoic | Permian [Ochoa]) at surface, covers < 0.1 % of this area

Tessey Limestone

Cretaceous rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Cretaceous rocks, undivided

gypsite deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers < 0.1 % of this area

gypsite deposits

Lithology: evaporite

Word Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Word Formation

Lost Creek Gneiss (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Lost Creek Gneiss

Tm2 and Tm3 units of Morita Ranch Formation (possibly from Cienega Mountain area) (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

Tm2 and Tm3 units of Morita Ranch Formation (possibly from Cienega Mountain area)

Lithology: basalt; trachyte

Benevides Formation and Finlay Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

Benevides Formation and Finlay Limestone, undivided

Lithology: limestone; sandstone; shale

upper part of Shely Group, including Tm4 or Morita Ranch Formation (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

upper part of Shely Group, including Tm4 or Morita Ranch Formation

Lithology: rhyolite; basalt

pre-Brazos River rocks, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines]) at surface, covers < 0.1 % of this area

pre-Brazos River rocks, undivided

Ranger Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers < 0.1 % of this area

Ranger Limestone

Lithology: limestone; shale

unnamed Pliocene deposits (Phanerozoic | Cenozoic | Tertiary | Pliocene) at surface, covers < 0.1 % of this area

unnamed Pliocene deposits

Lithology: sand; gravel; silt

Tarantula Gravel (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers < 0.1 % of this area

Tarantula Gravel

Yates Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Yates Formation

Duck Creek Limestone (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

Duck Creek Limestone

Lithology: limestone

Admiral and Coleman Junction Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Admiral and Coleman Junction Formations, undivided

Eagle Ford Formation and Buda Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Eagle Ford Formation and Buda Limestone, undivided

Devils Graveyard volcanic rocks (Phanerozoic | Cenozoic | Tertiary | Eocene Oligocene) at surface, covers < 0.1 % of this area

Devils Graveyard volcanic rocks

Lithology: tuff; basalt

Comanche Peak Limestone and Walnut Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Comanche Peak Limestone and Walnut Clay, undivided

Bell Canyon, Cherry Canyon, and Brushy Canyon Formations undivided (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Bell Canyon, Cherry Canyon, and Brushy Canyon Formations undivided

Seven Rivers Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Seven Rivers Formation

Cow Creek Limestone, Hammett Shale, and Sycamore Sand, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Cow Creek Limestone, Hammett Shale, and Sycamore Sand, undivided

igneous rocks of Austin age (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

igneous rocks of Austin age

Lithology: basalt; pyroclastic

Carlsbad Group (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Carlsbad Group

Lithology: limestone; sandstone

Ector Chalk (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Ector Chalk

Lithology: limestone

Chico Ridge Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers < 0.1 % of this area

Chico Ridge Limestone

Lithology: limestone

Edwards Limestone and Antlers Sand, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Edwards Limestone and Antlers Sand, undivided

Fusselman Dolomite (Phanerozoic | Paleozoic | Silurian) at surface, covers < 0.1 % of this area

Fusselman Dolomite

Moodys Branch Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Late) at surface, covers < 0.1 % of this area

Moodys Branch Formation

Lithology: mudstone

Upson Clay (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Upson Clay

Lithology: clay or mud

Tule Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers < 0.1 % of this area

Tule Formation

Lithology: sand; silt; clay or mud

Double Lakes Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene [Early Wisconsinan]) at surface, covers < 0.1 % of this area

Double Lakes Formation

Lithology: sand; gravel

Loma Plata Formation (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

Loma Plata Formation

Lithology: limestone; shale

Goat Seep Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Goat Seep Formation

Lithology: limestone ; sandstone

Cathederal Mountain Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers < 0.1 % of this area

Cathederal Mountain Formation

Allamore Formation (preCambrian-Proterozoic [Grenville]) at surface, covers < 0.1 % of this area

Allamore Formation

Big Branch Gneiss (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Big Branch Gneiss

Lithology: gneiss; schist

South Rim Formation from Pine Canyon Caldera (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

South Rim Formation from Pine Canyon Caldera

Santana Tuff from Sierra Rica caldera in Mexico (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

Santana Tuff from Sierra Rica caldera in Mexico

Lithology: ash-flow tuff

Van Horn Sandstone (preCambrian-Proterozoic [Grenville]) at surface, covers < 0.1 % of this area

Van Horn Sandstone

Yearwood Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Yearwood Formation

Carrizo Mountain Group showing metasedimentary rocks (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Carrizo Mountain Group showing metasedimentary rocks

San Carlos Sandstone (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

San Carlos Sandstone

Lithology: sandstone; coal

Black Gap area volcanic rocks (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers < 0.1 % of this area

Black Gap area volcanic rocks

Lithology: tuff; basalt

Ventioner Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Missouri]) at surface, covers < 0.1 % of this area

Ventioner Formation

Duff Formation, Decie Member from Paisano caldera (Phanerozoic | Cenozoic | Tertiary | Oligocene-Early) at surface, covers < 0.1 % of this area

Duff Formation, Decie Member from Paisano caldera

Willow Point Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missouri]) at surface, covers < 0.1 % of this area

Willow Point Formation

Lithology: limestone

Espy Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Espy Formation

Lithology: limestone; shale; sandstone

Gaptank Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Early Pennsylvanian-Middle Pennsylvanian-Late) at surface, covers < 0.1 % of this area

Gaptank Formation

Montoya Dolomite (Phanerozoic | Paleozoic | Ordovician-Middle Ordovician-Late) at surface, covers < 0.1 % of this area

Montoya Dolomite

Munn Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Munn Formation

Canyon Group, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Late [Missouri]) at surface, covers < 0.1 % of this area

Canyon Group, undivided

Gulfian rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Gulfian rocks, undivided

Lithology: mudstone; shale; limestone

Tansill Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Tansill Formation

Comanche Peak Limestone, Walnut Clay, and Antlers Sand, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Comanche Peak Limestone, Walnut Clay, and Antlers Sand, undivided

Bissett Conglomerate (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Bissett Conglomerate

Carrizo Mountain Group showing metaigneous rocks (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Carrizo Mountain Group showing metaigneous rocks

Buda Limestone and San Martine Member of Borache Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Buda Limestone and San Martine Member of Borache Limestone, undivided

Lithology: limestone; shale

Buda Limestone and Eagle Mountain Sandstone, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

Buda Limestone and Eagle Mountain Sandstone, undivided

Quitman Mountains caldera volcanic rocks and volcanic rocks of sneed (Cox) Mountain and west of Victorio Peak (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

Quitman Mountains caldera volcanic rocks and volcanic rocks of sneed (Cox) Mountain and west of Victoria Peak

Granite (preCambrian-Proterozoic [Grenville]) at surface, covers < 0.1 % of this area

Granite

Lithology: granite

Blanco Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene) at surface, covers < 0.1 % of this area

Blanco Formation

Shafter Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Shafter Formation

Pleistocene and Pliocene deposits, undifferentiated (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene) at surface, covers < 0.1 % 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.

Toy Limestone (Phanerozoic | Cenozoic | Quaternary | Pleistocene-Early(?)) at surface, covers < 0.1 % of this area

Toy Limestone

Lithology: limestone

Hannold Hill Member of Tornillo Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Hannold Hill Member of Tornillo Formation

Van Horn Mountains caldera volcanic rocks (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Van Horn Mountains caldera volcanic rocks

Comanchean rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Early [Washita]) at surface, covers < 0.1 % of this area

Comanchean rocks, undivided

Fingers Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene) at surface, covers < 0.1 % of this area

Fingers Formation

Lithology: indeterminate

Pinto Canyon Formation (Phanerozoic | Paleozoic | Permian [Leonard Guadalupe]) at surface, covers < 0.1 % of this area

Pinto Canyon Formation

Lithology: limestone; siltstone; chert

Eocene volcanic rocks (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers < 0.1 % of this area

Eocene volcanic rocks

Lithology: rhyolite

Rhyolite (preCambrian-Proterozoic [Grenville]) at surface, covers < 0.1 % of this area

Rhyolite

Lithology: rhyolite; porphyry

Helms Shale, Rancheria Formation, Las Cruces Limestone, Percha Shale, and Canutillo Formations, undivided (Phanerozoic | Paleozoic | Devonian Carboniferous Mississippian-Late [Chesteran]) at surface, covers < 0.1 % of this area

Helms Shale, Rancheria Formation, Las Cruces Limestone, Percha Shale, and Canutillo Formations, undivided

Edwards and Comanche Peak Limestones, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Edwards and Comanche Peak Limestones, undivided

Onion Creek Marl (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers < 0.1 % of this area

Onion Creek Marl

Lithology: sand; gravel; clay or mud

Alta Formation (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Alta Formation

Lithology: sandstone; shale

Lenox Hills and Neal Ranch Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Lenox Hills and Neal Ranch Formations, undivided

Malone Formation (Phanerozoic | Mesozoic | Jurassic-Late) at surface, covers < 0.1 % of this area

Malone Formation

Del Carmen Limestone (Phanerozoic | Mesozoic | Cretaceous-Early ) at surface, covers < 0.1 % of this area

Del Carmen Limestone

Lithology: limestone

Black Peaks Member of Tornillo Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers < 0.1 % of this area

Black Peaks Member of Tornillo Formation

Lithology: sandstone; clay or mud

Duck Creek Limestone and Kiamichi Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Duck Creek Limestone and Kiamichi Formation, undivided

Lithology: limestone; clay or mud

Presidio Formation (Phanerozoic | Mesozoic | Cretaceous-Early [Aptian Albian]) at surface, covers < 0.1 % of this area

Presidio Formation

Llanoria Quartzite (preCambrian-Proterozoic [Grenville]) at surface, covers < 0.1 % of this area

Llanoria Quartzite

Cienequita Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle Pennsylvanian-Late) at surface, covers < 0.1 % of this area

Cienequita Formation

Red Mountain Gneiss (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Red Mountain Gneiss

Lithology: gneiss; granite; granite

Mafic igneous rocks (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Mafic igneous rocks

Ross Mine Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Ross Mine Formation

Ordovician rocks, undivided (Phanerozoic | Paleozoic| Ordovician) at surface, covers < 0.1 % of this area

Ordovician rocks, undivided

Lithology: limestone; shale

Coal Creek Serpentinite (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Coal Creek Serpentinite

Lithology: serpentinite

Nash Creek Formation (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

Nash Creek Formation

Lithology: indeterminate

Castile Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Castile Formation; dominantly anhydrite sequence; Upper Permian

Lithology: evaporite; limestone

Reklaw Formation, Carrizo Sand, and Wilcox and Midway Groups, undivided (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers < 0.1 % of this area

Reklaw Formation, Carrizo Sand, and Wilcox and Midway Groups, undivided

Ogallala Formation (Phanerozoic | Cenozoic | Tertiary | Pliocene) at surface, covers < 0.1 % 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.

Dewey Lake Red beds (Phanerozoic | Paleozoic | Permian [Ochoa]) at surface, covers < 0.1 % of this area

Dewey Lake Red beds

alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Alluvium; upper and middle Quaternary

Lithology: alluvium

piedmont alluvial deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Piedmont alluvial deposits: upper and middle Quaternary; includes deposits of higher gradient tributaries bordering major stream valleys, alluvial veneers of the piedmont slope, and alluvial fans

Lithology: alluvium

Briggs Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers < 0.1 % of this area

Briggs Formation

unnamed Pennsylvanian rocks (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers < 0.1 % of this area

unnamed Pennsylvanian rocks

Lithology: shale; limestone; sandstone

Permian rocks, undivided (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Permian rocks, undivided

Cloud Chief Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Cloud Chief Formation

Lithology: evaporite; shale; sandstone

Torcer Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Torcer Formation

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % 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

Lithology: alluvium

upper Cretaceous rocks, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % of this area

upper Cretaceous rocks, undivided

Sue Peaks Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Sue Peaks Formation

Lithology: limestone; shale; mudstone

Paleozoic rocks, undivided (Phanerozoic | Paleozoic) at surface, covers < 0.1 % of this area

Paleozoic rocks, undivided

Mina Grande Formation (Phanerozoic | Paleozoic | Permian [Guadalupe]) at surface, covers < 0.1 % of this area

Mina Grande Formation

Lithology: limestone

Morrison Formation (Phanerozoic | Mesozoic | Jurassic-Late) at surface, covers < 0.1 % of this area

Morrison Formation

Lithology: shale; sandstone

Etholen Conglomerate (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Etholen Conglomerate

Cibolo Formation (Phanerozoic | Paleozoic | Permian [Leonard]) at surface, covers < 0.1 % of this area

Cibolo Formation

Lithology: limestone; shale

Dakota and Purgatoir Formations, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Dakota and Purgatoir Formations, undivided

Lithology: sandstone; shale; coal

Artesia Group (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Artesia Group; shelf facies forming broad south-southeast trending outcrop from Glorieta to Artesia area; includes Grayburg, Queen, Seven Rivers, Yates, and Tansill Formations; Guadalupian. May locally include Moenkopi Formation (Triassic) at top

Alluvium - Alluvial deposits in major stream channels or in mappable meanders of major streams (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

Alluvial deposits in major stream channels or in mappable meanders of major streams - Includes alluvial deposits in natural levees in some areas.

Lithology: alluvium

San Carlos Tuff from San Carlos caldera in Mexico (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers < 0.1 % of this area

San Carlos Tuff from San Carlos caldera in Mexico

Lithology: ash-flow tuff

Mundy Breccia and Castner Limestone, undivided (preCambrian-Proterozoic) at surface, covers < 0.1 % of this area

Mundy Breccia and Castner Limestone, undivided

Benevides Formation (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

Benevides Formation

Lithology: sandstone

Rustler Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Rustler Formation; siltstone, gypsum, sandstone, and dolomite; Upper Permian

Mississippi, Devonian, and Ordovician rocks, undivided (Phanerozoic | Paleozoic | Ordovician Devonian Carboniferous Mississippian) at surface, covers < 0.1 % of this area

Mississippi, Devonian, and Ordovician rocks, undivided

Sedwick and Moran Formations, undivided (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers < 0.1 % of this area

Sedwick and Moran Formations, undivided

Miocene intrusive rocks (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers < 0.1 % of this area

Miocene intrusive rocks

Lithology: basalt

Salado Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Salado Formation; evaporite sequence; Upper Permian

Lithology: evaporite; sandstone

San Andres Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

San Andres Formation; limestone and dolomite with minor shale; Guadalupian in south, in part Leonardian to north

Bell Canyon Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Bell Canyon Formation; basin facies-sandstone, limestone, and shale; Guadalupian

Lithology: sandstone; limestone; shale

eolian deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Eolian deposits

Lithology: eolian

Capitan Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Capitan Formation; Upper Guadalupian age limestone (reef facies)

Lithology: carbonate

intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Tertiary intrusive rocks; undifferentiated

Ogallala Formation (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

Ogallala Formation, alluvial and eolian deposits, and petrocalcic soils of the southern High Plains; Lower Pliocene to middle Miocene (locally includes unit Qoa)

Lithology: alluvium; eolian; carbonate

Quartermaster Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Quartermaster Formation; red sandstone and siltstone; Upper Permian

Seven Rivers Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Seven Rivers Formation; gypsum, anhydrite, salt, dolomite, and siltstone; Guadalupian

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % 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

Lithology: alluvium

Permian rocks undifferentiated (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % 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

Cutoff Shale (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Cutoff Shale; in Brokeoff Mountains only

Lithology: shale

Cherry Canyon Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Cherry Canyon Formation; basin facies-sandstone, limestone, and shale

Lithology: sandstone; limestone; shale

Victoria Peak Limestone (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Victorio Peak Limestone; in Brokeoff Mountains only

Lithology: limestone

Dakota Formation (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Late) at surface, covers < 0.1 % of this area

Dakota Formation

Lithology: sandstone; shale; coal

older alluvial deposits of upland plains and piedmont areas (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Older alluvial deposits of upland plains and piedmont areas, and calcic soils and eolian cover sediments of High Plains region; includes scattered lacustrine, playa, and alluvial deposits of the Tahoka, Double Tanks, Tule, Blanco, Blackwater Draw, and Gatuna Formations, the latter of which may be Pliocene at base; outcrops, however, are basically of Quaternary deposits; upper Quaternary to uppermost Pliocene(?)

Lithology: alluvium

Chenier Plain, Saline Marsh (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

gray to brown to black clay and silt of moderate organic content.

Lithology: clay or mud; silt

Terrace Deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers < 0.1 % 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

Lithology: sand; gravel; volcanic ash

Caddo Formation (Phanerozoic | Mesozoic | Cretaceous-Early ) at surface, covers < 0.1 % 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

Lithology: limestone; shale

Grayburg and Queen Fromations (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Grayburg and Queen Formations; sandstone, gypsum, anhydrite, dolomite, and red mudstone; Guadalupian

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

gray to brownish gray clay and silty clay, reddish brown in the Red River Valley, some sand and gravel locally.

Lithology: clay or mud; sand; gravel

Dune Sand (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers < 0.1 % 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).

Lithology: sand

Hueco Formation (Phanerozoic | Paleozoic | Permian) at surface, covers < 0.1 % of this area

Hueco Formation; limestone unit restricted to south-central area; Pendejo Tongue divides Abo Formation into upper and lower parts; Wolfcampian

Alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers < 0.1 % of this area

Alluvium - Alluvial deposits of present streams

Lithology: alluvium

Mississippian and Devonain rocks, undivided (Phanerozoic | Paleozoic | Devonian Carboniferous Mississippian) at surface, covers < 0.1 % of this area

Mississippian and Devonian rocks, undivided; includes the Lake Valley Limestone, Caballero, Las Cruces, Rancheria, and Helms Formations and Escabrosa Group; Mississippian; the Onate, Sly Gap, Contadero Formations, and Percha Shale of south-central New Mexico, and Canutillo Formation of Northern Franklin Mountains and Bishops Cap area; Devonian

Antlers Sand or Antlers Sandstone (Phanerozoic | Mesozoic | Cretaceous-Early ) at surface, covers < 0.1 % 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.

Silurian and Ordovician rocks, undivided (Phanerozoic | Paleozoic | Ordovician Silurian) at surface, covers < 0.1 % of this area

Silurian and Ordovician rocks, undivided

Lithology: sedimentary rock

Pennsylvanian rocks, undivided (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers < 0.1 % of this area

Pennsylvanian rocks, undivided; in Sangre de Cristo Mountains may include Sandia Formation, Madera Limestone, La Pasada, Alamitos, and Flechado Formations; elsewhere may include Bar-B, Nakaye, Red House, Oswaldo, and Syrena Formations

Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers < 0.1 % 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.

upper Chinle Group (Garita Creek, Trujillo, Bull Canyon, and Redonda Formations) (Phanerozoic | Mesozoic | Triassic) at surface, covers < 0.1 % of this area

Upper Chinle Group, Garita Creek through Redonda Formations, undivided

lacustrine and playa-lake deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Lacustrine and playa-lake deposits; includes associated alluvial and eolian deposits of major lake basins; upper Quaternary