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Washita Group

Washita Group
State Texas
Name Washita Group
Geologic age Phanerozoic | Mesozoic | Cretaceous-Early [Comanchean] Cretaceous-Late
Comments Washita Group--alternating thick clay units and thin limestone units; clay, calcar, commonly sandy, dk bluish gray and black; limestone in lower part hard, bluish gray to shtie, in upper part soft, thickbedded; marine megafossils; thickness 200 ft.
Primary rock type clay or mud
Secondary rock type limestone
Other rock types
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone (Bed)
Sedimentary > Clastic > Mudstone > Claystone (Bed)
Map references
Bureau of Economic Geology, 1992, Geologic Map of Texas: University of Texas at Austin, Virgil E. Barnes, project supervisor, Hartmann, B.M. and Scranton, D.F., cartography, scale 1:500,000
Unit references
Bureau of Economic Geology, 1966, Texarkana Sheet, Geologic Atlas of Texas, University of Texas, Bureau of Economic Geology, scale 1:250,000.
Bureau of Economic Geology, 1976, Hobbs Sheet, Geologic Atlas of Texas: University of Texas at Austin, Bureau of Economic Geology, scale 1:250,000.
Counties Brewster - Crockett - Jeff Davis - Pecos - Reeves - Upton