No current usage.
(†Middle Creek limestone ledge (informal) in Graneros Formation (SD) replaced with Orman Lake Limestone Member of Greenhorn Formation. See Orman Lake.)
Late Cretaceous
Not designated. Named from exposures on northeast side of valley of Middle Creek, in T. 9 N., R. 1 and 2 E., Butte Co., SD (Wing, 1940).
Williston 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 ([ ]).