|Geologic age||Late Cretaceous; Gulfian Series|
Sedimentary > Clastic > Mudstone > Claystone (Bed)
|Comments||mapped in Ouachita tectonic belt province, eastern Dallas, east-central Ellis, and northeast Hill Cos., TX and east Texas basin, Rockwall, Kaufman, and Navarro Cos. Clay, calcareous, silt and sand content incre. up, montmorillonitic, blocky, conchoidal fracture, med. gray; some glaucontie, phosphate pellets, hematite and pyrite nodules; v. thin ls lenses locally in lower part; grades up to Wolfe City Fm., thickness 500 +- ft.|
|Stratigraphic units||lower Taylor Marl|
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, 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||Bell - Collin - Dallas - Delta - Ellis - Falls - Fannin - Hays - Hill - Hunt - Lamar - McLennan - Navarro - Red River - Rockwall - Travis - Williamson|