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

Geologic units in Bastrop county, Texas

Hooper Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 6 % of this area

Hooper Formation

Lithology: mudstone; sandstone

Queen City Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 9 % of this area

Queen City Sand

Lithology: sandstone; siltstone; clay or mud; sand

Yegua Formation (Phanerozoic | Cenozoic | Tertiary | Eocene-Middle) at surface, covers 1 % of this area

Yegua Formation

Lithology: clay or mud; sandstone; limestone; coal

Sparta Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 6 % of this area

Sparta Sand

Lithology: sand; clay or mud; silt; sandstone; coal

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

Terrace deposits

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

Midway Group, undivided (Phanerozoic | Cenozoic | Tertiary | Paleocene) at surface, covers 4 % of this area

Midway Group, undivided

Lithology: fine-grained mixed clastic; limestone; mudstone

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

Weches Formation

Lithology: sand; clay or mud

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

Navarro and Taylor Groups, undivided

Lithology: clay or mud; fine-grained mixed clastic; sandstone; limestone

Reklaw Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 8 % of this area

Reklaw Formation

Lithology: sandstone; clay or mud

Cook Mountain Formation (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 6 % of this area

Cook Mountain Formation

Lithology: clay or mud; sandstone; coal

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

alluvium

Lithology: sand; silt; clay or mud; gravel

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

Willis Formation

Lithology: clay or mud; silt; sand; gravel

Navarro Group and Marlbrook Marl, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 1 % of this area

Navarro Group and Marlbrook Marl, undivided

Lithology: clay or mud; fine-grained mixed clastic; sandstone; sand

Wilcox Group, undivided (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers 14 % of this area

Wilcox Group, undivided

Lithology: fine-grained mixed clastic; coal; sand; clay or mud

Carizzo Sand (Phanerozoic | Cenozoic | Tertiary | Eocene) at surface, covers 6 % of this area

Carizzo Sand

Lithology: sandstone

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

Simsboro Formation

Lithology: sand; mudstone

high gravel deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene) at surface, covers 3 % of this area

high gravel deposits

Lithology: gravel; silt; sand

Calvert Bluff Formation (Phanerozoic | Cenozoic | Tertiary | Paleocene Eocene) at surface, covers 12 % of this area

Calvert Bluff Formation

Lithology: mudstone; sandstone; coal