Pg. B53-B59. Difficulty Shale Member of Goose Egg Formation. Freezeout Tongue of Chugwater Formation of Thomas (1934) is divided into an upper and a lower part of eastward extension of Ervay Member of Park City Formation. Because of this division of the Freezeout by the Ervay the concept of the Freezeout as a tongue is untenable. Freezeout is herein revised. Lower part is named Difficulty Shale Member. Mostly moderate-red dish-orange parallel laminated and thinly bedded mudstone and siltstone. Thickness commonly about 50 feet. Overlies Forelle Limestone Member; underlies Ervay Member. Age is Late Permian.
Type section: in Freezeout Hills, in SW/4 sec. 10, T. 24 N., R. 80 W., [Carbon Co.], southeastern WY, about 0.25 mi northeast of location of old Difficulty Post Office, and seems to be in same location as section described near Difficulty by Thomas.

Source: US geologic names lexicon (USGS Bull. 1350, p. 210).