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Mineral Resources > Online Spatial Data > Geology > by state > Texas Geology

Geologic units in El Paso county, Texas

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

Lithology: sedimentary rock; medium-grained mixed clastic; carbonate

alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 15 % of this area

alluvium

Lithology: sand; silt; clay or mud; gravel

Quaternary-Tertiary bolson deposits (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene) at surface, covers 7 % of this area

Quaternary-Tertiary bolson deposits

Lithology: clay or mud; silt; sandstone; conglomerate

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

dune sand sheet deposits

Lithology: sand; silt

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

Lithology: limestone; shale; conglomerate

Llanoria Quartzite (preCambrian-Proterozoic [Grenville]) at surface, covers 0.4 % of this area

Llanoria Quartzite

Lithology: quartzite; sandstone; siltstone; shale

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

Lithology: carbonate; medium-grained mixed clastic

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

Alluvium; upper and middle Quaternary

Lithology: alluvium

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

Magdalena Formation

Lithology: limestone; shale

El Paso Formation and Bliss Sandstone, undivided (Phanerozoic | Paleozoic| Cambrian-Furongian(?) Ordovician-Early) at surface, covers 1 % of this area

El Paso Formation and Bliss Sandstone, undivided

Lithology: limestone; dolostone (dolomite); sandstone; conglomerate

Granite (preCambrian-Proterozoic [Grenville]) at surface, covers 0.9 % of this area

Granite

Lithology: granite

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

Paleozoic rocks, undivided

Lithology: limestone; shale; mixed clastic/carbonate

Panther Seep Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers < 0.1 % of this area

Panther Seep Formation; Organ, Franklin, and San Andres Mountains

Lithology: fine-grained mixed clastic; limestone; evaporite

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

Cretaceous rocks, undivided

Lithology: limestone; shale; sandstone; mudstone

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

older alluvial deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 8 % of this area

older alluvial deposits

Lithology: gravel; sand; silt

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

Mundy Breccia and Castner Limestone, undivided

Lithology: limestone; basalt; hornfels; conglomerate; dolostone (dolomite); diabase

Fusselman Dolomite (Phanerozoic | Paleozoic | Silurian) at surface, covers 0.5 % of this area

Fusselman Dolomite

Lithology: dolostone (dolomite); limestone

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

Eocene intrusive rocks

Lithology: basalt; trachyte; felsic volcanic rock; rhyolite; phonolite; latite; trachyandesite

Montoya Dolomite (Phanerozoic | Paleozoic | Ordovician-Middle Ordovician-Late) at surface, covers 0.4 % of this area

Montoya Dolomite

Lithology: dolostone (dolomite); limestone; sandstone

Oligocene intrusive rocks (Phanerozoic | Cenozoic | Tertiary | Oligocene) at surface, covers 0.4 % of this area

Oligocene intrusive rocks

Lithology: basalt; trachyte; felsic volcanic rock; rhyolite; phonolite; latite; trachyandesite

Rhyolite (preCambrian-Proterozoic [Grenville]) at surface, covers 0.3 % 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 0.2 % of this area

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

Lithology: limestone; shale; chert; sandstone

alluvial fan deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 10 % of this area

alluvial fan deposits

Lithology: alluvial fan

Mingus Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Des Moines]) at surface, covers 1 % of this area

Mingus Formation

Lithology: shale; sandstone; limestone; coal

bolson deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 13 % of this area

bolson deposits

Lithology: clay or mud; silt; sand; evaporite

Upper Santa Fe Group (Phanerozoic | Cenozoic | Tertiary Quaternary) at surface, covers < 0.1 % of this area

Upper Santa Fe Group. Includes Camp Rice, Fort Hancock, Palomas, Sierra Ladrones, Ancha, Puye, and Alamosa Formations; middle Pleistocene to uppermost Miocene

Lithology: clastic; unconsolidated deposit; mixed clastic/volcanic

sand sheet deposits (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 32 % of this area

sand sheet deposits

Lithology: sand; silt

Hueco Limestone (Phanerozoic | Paleozoic | Permian [Wolfcamp]) at surface, covers 3 % of this area

Hueco Limestone

Lithology: limestone; dolostone (dolomite); sandstone; shale; mudstone; conglomerate