|Geologic age||Late Cretaceous; Gulfian Series|
Sedimentary > Clastic > Mudstone > Claystone (Bed)
|Comments||Clay, calcareous, silty, poorly bedded to massive; marine megafossils scarce; thickness 80 ft, feathers out west near Bonham.|
Bureau of Economic Geology, 1967, Sherman Sheet, Geologic Atlas of Texas: University of Texas at Austin, Bureau of Economic Geology, 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.
|Counties||Fannin - Lamar - Red River|