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

Geologic units in Hill county, Texas

Quaternary deposit, undivided (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.2 % 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

Austin Chalk (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 13 % of this area

Austin Chalk

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

lower part of Washita Group (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers < 0.1 % of this area

lower part of Washita Group

Lithology: limestone; mudstone

Woodbine Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 14 % of this area

Woodbine Formation

Lithology: shale; sand; clay or mud; limestone; coal; tuff

undivided part of Washita Group (Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean]) at surface, covers 6 % of this area

undivided part of Washita Group

Lithology: clay or mud; limestone; mudstone

Eagle Ford Formation (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 23 % of this area

Eagle Ford Formation

Lithology: shale; siltstone; limestone

Neylandville and Marlbrook Marls, undivided (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 0.3 % of this area

Neylandville and Marlbrook Marls, undivided

Lithology: clay or mud

Wolfe City Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 9 % of this area

Wolfe City Formation

Lithology: sand; silt; mudstone

Ozan Formation (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers 15 % of this area

Ozan Formation

Lithology: clay or mud

Pecan Gap Chalk (Phanerozoic | Mesozoic | Cretaceous-Late [Gulfian]) at surface, covers < 0.1 % of this area

Pecan Gap Chalk

Lithology: limestone; sand; clay or mud; limestone

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

Terrace deposits

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

alluvium (Phanerozoic | Cenozoic | Quaternary | Holocene) at surface, covers 3 % of this area

alluvium

Lithology: sand; silt; clay or mud; gravel

undivided part Fredericksberg Group (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 2 % of this area

undivided part Fredericksberg Group

Lithology: clay or mud; limestone; mudstone; shale

Grayson Marl and Main Street Limestone, undivided (Phanerozoic | Mesozoic | Cretaceous-Early Cretaceous-Late) at surface, covers 9 % of this area

Grayson Marl and Main Street Limestone, undivided

Lithology: mudstone; limestone