|Name||Pre-Brazos River rocks, undivided|
|Geologic age||Pennsylvanian; Des Moines Series|
Sedimentary > Clastic > Mudstone > Shale > Black-shale (Bed)in Leon and Sabana River Valleys contains thin ss units with a few limestone lentils
|Comments||mostly mudstone with thin sandstone units and a few limestone lentils|
Bureau of Economic Geology, 1972, Abilene sheet, Geologic Atlas of Texas, Bureau of Economic Geology, University of Texas at Austin, scale 1:250,000.
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.