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

Geologic units in Comal county, Texas

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

Austin Chalk

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

Glen Rose Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 50 % of this area

Glen Rose Limestone

Lithology: limestone; clay or mud; sandstone; conglomerate

Eagle Ford Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 0.4 % of this area

Eagle Ford Formation

Lithology: shale; siltstone; limestone

Leona Formation (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 3 % of this area

Leona Formation

Lithology: sand; gravel; clay or mud

Hensell Sand (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean) at surface, covers 2 % of this area

Hensell Sand

Lithology: limestone; sand; conglomerate; shale

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

Pecan Gap Chalk

Lithology: limestone; sand; clay or mud; limestone

Edwards Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 29 % of this area

Edwards Limestone

Lithology: limestone; dolostone (dolomite); chert

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

Terrace deposits

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

Buda Limestone and Del Rio Clay, undivided (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 4 % of this area

Buda Limestone and Del Rio Clay, undivided

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

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

alluvium

Lithology: sand; silt; clay or mud; gravel