Skinner Ranch and Hess Formations, undivided (TXPsh;0)

State	Texas
Name	Skinner Ranch and Hess Formations, undivided
Geologic age	Phanerozoic \| Paleozoic \| Permian [Wolfcamp]
Original map label	Psh
Comments	Skinner Ranch Fm--calcarenite, biohermal ls., coarsely granular, massive, thick beds of limestone-pebble conglomerate in lower part, minor amounts of interbedded yellow sandy shale, some pink-brown chert; numerous brachiopods and fusulinids; type section west knob of Leonard Mountain (11 km north of Marathon, Brewster Co.); thickness 225-1,600 ft; merges eastward with thin-bedded Hess Limestone, much of which is dolomitized; thickness 1,600-2,300 ft.
Primary rock type	limestone
Secondary rock type	dolostone (dolomite)
Other rock types	shale; conglomerate
Lithologic constituents	Major Sedimentary > Carbonate > Limestone (Bed) Minor Sedimentary > Clastic > Mudstone > Shale (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, 1982, Fort Stockton Sheet, Geologic Atlas of Texas, University of Texas at Austin, scale 1:250,000. Cooper, G.A. and Grant, R.E., 1966, Permian rock units in the Glass Mountains, west Texas: Geological Survey Bulletin 1244-E. [http://pubs.er.usgs.gov/publication/b1244E] Cooper, G.A. and Grant, R.E., 1972, Permian brachiopods of West Texas, I., in Smithsonian Contributions to Paleobiology no. 14.
Geographic coverage	Brewster - Pecos