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

Geologic units in Lampasas county, Texas

Honeycut Formation (Phanerozoic | Paleozoic | Ordovician-Early) at surface, covers 2 % of this area

Honeycut Formation

Lithology: dolostone (dolomite); limestone

undivided part Fredericksberg Group (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 5 % of this area

undivided part Fredericksberg Group

Lithology: clay or mud; limestone; mudstone; shale

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

alluvium

Lithology: sand; silt; clay or mud; gravel

Strawn Group (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atoka Des Moines]) at surface, covers 3 % of this area

Strawn Group

Lithology: shale; sandstone; clay or mud; sandstone; conglomerate; coal

Barnett Formation, Chappel Limestone, Houy, Zesch, Bear Spring, and Stribling Formations, and Pillar Bluff Limestone, undivided (Phanerozoic | Paleozoic | Devonian Carboniferous Mississippian-Early Mississippian-Middle Mississippian-Late) at surface, covers 0.4 % of this area

Barnett Formation, Chappel Limestone, Houy, Zesch, Bear Spring, and Stribling Formations, and Pillar Bluff Limestone, undivided

Lithology: limestone; shale; phosphorite; dolostone (dolomite); chert

Gorman Formation (Phanerozoic | Paleozoic| Ordovician-Early) at surface, covers 0.9 % of this area

Gorman Formation

Lithology: limestone; dolostone (dolomite)

Tanyard Formation (Phanerozoic | Paleozoic | Ordovician-Early) at surface, covers 0.2 % of this area

Tanyard Formation

Lithology: limestone; dolostone (dolomite)

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

Paluxy Sand and Glen Rose Limestone, undivided

Lithology: sandstone; limestone; claystone

Travis Peak Formation (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 9 % of this area

Travis Peak Formation

Lithology: conglomerate; sandstone; limestone

Quaternary deposit, undivided (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.5 % 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

Smithwick Formation (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian-Middle [Atoka]) at surface, covers 0.5 % of this area

Smithwick Formation

Lithology: fine-grained mixed clastic; limestone; shale; sandstone; conglomerate

Marble Falls Limestone (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian [Morrow]) at surface, covers 3 % of this area

Marble Falls Limestone

Lithology: limestone; shale

Walnut Clay (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 21 % of this area

Walnut Clay

Lithology: clay or mud; limestone; shale

Terrace deposits (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 1 % of this area

Terrace deposits

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

undivided parts of Washita and Fredericksberg Groups (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers 0.4 % of this area

undivided parts of Washita and Fredericksberg Groups

Lithology: clay or mud; limestone; mudstone; shale

Glen Rose Limestone (Phanerozoic | Mesozoic | Cretaceous-Early) at surface, covers < 0.1 % of this area

Glen Rose Limestone

Lithology: limestone; clay or mud; sandstone; conglomerate