Geology of the Shotgun Butte area, Fremont County, Wyoming

Stratigraphic cross sections of the Mowry Shale and associated strata in the Wind River Basin, Wyoming

“…These units accumulated in tidal flats and represent the initial transgression of the Cretaceous sea during the Albian (May, 1992). While most authors consider the "rusty beds" the basal part of the Thermopolis Shale (Washburne, 1908;Burk, 1956;Eicher, 1960Eicher, , 1962Mirsky, 1962;May 1992;May and others 1995), Love (1948) and Keefer and Troyer (1964) included the "rusty beds" with the underlying Cloverly Formation. The Thermopolis Shale, including the "rusty beds," ranges in thickness from 90 to about 220 ft.…”

“…3, 4, and map sheet). The Mowry Shale consists of a lower soft clay-rich shale (originally the upper Thermopolis shale unit of Lupton, 1916) and an upper hard siliceous unit (Keefer and Troyer, 1964;Keefer, 1997). The combined thickness of the lower and upper units ranges from less than 250 ft in the southeastern part of the basin to greater than 625 ft in the northwestern part (fig.…”