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

Geologic units in Terrell county, Texas

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

Permian rocks, undivided

Lithology: shale; sandstone; evaporite; dolostone (dolomite); siltstone

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

alluvium

Lithology: sand; silt; clay or mud; gravel

Buda Limestone and Del Rio Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 6 % of this area

Buda Limestone and Del Rio Clay, undivided

Lithology: limestone; mudstone; clay or mud; siltstone; shale

Bouquillas Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 11 % of this area

Bouquillas Formation

Lithology: limestone; shale; mudstone; siltstone

Uvalde Gravel (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene) at surface, covers < 0.1 % of this area

Uvalde Gravel

Lithology: gravel; chert

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

alluvial fan deposits

Lithology: alluvial fan

Edwards Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 51 % of this area

Edwards Limestone

Lithology: limestone; dolostone (dolomite); chert

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

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

older alluvial deposits

Lithology: gravel; sand; silt

Sue Peaks Formation, Del Carmen Limestone, and Telephone Canyon Formation, undivided (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.2 % of this area

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

Lithology: limestone; shale

Buda Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 5 % of this area

Buda Limestone

Lithology: limestone

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

Quaternary deposit, undivided (Phanerozoic | Cenozoic | Quaternary) at surface, covers 12 % 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

Lithology: sand ; silt ; clay or mud; gravel; carbonate

Santa Elena Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 10 % of this area

Santa Elena Limestone

Lithology: limestone; mudstone; chert

Austin Chalk (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 5 % of this area

Austin Chalk

Lithology: limestone; mudstone; clay or mud; bentonite; mudstone

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

playa deposits

Lithology: clay or mud; silt