/Black Butte Tongue of Rock Springs Formation of Mesaverde Group (WY*)
Late Cretaceous (Campanian)*
Named from exposures along Black Butte Creek, in sec. 36, T. 18 N., R. 102 W., Sweetwater Co., southwestern WY (Hale, 1950).
Green River basin*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).