Usage:
No current usage.
(†Pedro Bentonite Bed of Mitten Member of Pierre Shale (SD,WY) replaced with Ardmore Bentonite Beds. See Ardmore.)
Geologic age:
Late Cretaceous
Type section, locality, area and/or origin of name:
Named from exposures near Pedro, in sec. 5, T. 45 N., R. 63 W., Weston Co., WY (Rubey, 1930).
AAPG geologic province:
Powder River basin
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 ([ ]).