Stratigraphy of Pennsylvanian and lower Permian rocks in Brown and Coleman Counties, Texas

Pennsylvanian and Lower Permian rocks of parts of west and central Texas; Petrography and environmental analysis of some Pennsylvanian limestones from central Texas

“…Some of the results of that more general study have been presented in papers by Bergenback and Terriere (1953), Myers,Stafford,and Burnside (19f3) Eargle (1960), Terriere (1960), and Myers (1960). The project was carried on in cooperation with the Bureau of Economic Geology, The University of Texas.…”

“…Limestone unit C of the Gunsight has been recognized over a large area in Brown and Coleman Counties (Eargle, 1960), but seems to be less persistent within the Grosvenor quadrangle than units such as unit D of the Bluff Creek, whose lateral continuity and correlations are more in doubt.…”

Geology of the Grosvenor quadrangle, Brown and Coleman Counties, Texas

“…In 1950, the U.S. Geological Survey began a study of the Pennsylvanian and lower Permian strata of central and western Texas to determine the lithology, distribution, stratigraphic relationships, and conditions of deposition of these sedimentary rocks. Some of the results of that study have been presented in papers by Stafford, 1959, Burnside, 1959, Myers, Stafford, and Burnside (1956, Eargle (1960), and Myers (in press). This report on the geology of the Grosvenor quadrangle constitutes another in that series, and shows the areal distribution and lithologic character of some of the Pennsylvanian and lower Permian rocks on their outcrop in central Texas (pis.…”

“…These rocks belong to the Canyon and Cisco groups of Pennsylvanian age. Eargle (1960) discussed the stratigraphy of the Strawn, Canyon, and Cisco groups and the lower part of the Wichita group of Permian age, and revised many of the boundaries and nomenclature of their component formations, members, and beds. His usage is followed in this paper.…”

“…In the nomenclature of Eargle (1960), the Canyon group contains, in ascending order, the Graford, the Winchell, the Brad, and the Caddo Creek formations. The total thickness of the Canyon group in this area, as given by Eargle, is about 620 feet.…”