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

Geologic units in Zavala county, Texas

Bigford Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 14 % of this area

Bigford Formation

Lithology: siltstone; sandstone; clay or mud

Quaternary deposit, undivided (Phanerozoic | Cenozoic | Quaternary) at surface, covers 1 % 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

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

Escondido Formation

Lithology: shale; siltstone; sandstone

Laredo Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Middle) at surface, covers 13 % of this area

Laredo Formation

Lithology: sandstone; clay or mud

Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 9 % of this area

Terrace deposits

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

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

Kincaid Formation

Lithology: sand; clay or mud; limestone

Leona Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 16 % of this area

Leona Formation

Lithology: sand; gravel; clay or mud

Uvalde Gravel (Phanerozoic | Cenozoic | Tertiary Quaternary | Pliocene Pleistocene) at surface, covers 4 % of this area

Uvalde Gravel

Lithology: gravel; chert

El Pico Clay (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 22 % of this area

El Pico Clay

Lithology: clay or mud; sandstone; coal

Carizzo Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 7 % of this area

Carizzo Sand

Lithology: sandstone

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

alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 8 % of this area

alluvium

Lithology: sand; silt; clay or mud; gravel

Indio Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers 4 % of this area

Indio Formation

Lithology: fine-grained mixed clastic; coal