Usage:
Clay Spur Bentonite Bed of Mowry Shale (MT*,SD*,WY*)
Clay Spur Bentonite of Belle Fourche Shale (WY)
Geologic age:
early Late Cretaceous (Cenomanian)*
Type section, locality, area and/or origin of name:
Not designated. Named from exposures near Clay Spur, in sec. 30, T. 47 N., R. 63 W., Weston Co., WY (Rubey, 1931).
AAPG geologic province:
Central Montana uplift
Chadron arch
Powder River basin*
Williston basin*
Wind 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 ([ ]).