Usage:
No current usage.
(†Sheep Mountain Formation (MT) replaced with Pilcher Formation of Missoula Group of Belt Supergroup. See Pilcher.)
Geologic age:
Mesoproterozoic
Type section, locality, area and/or origin of name:
Upper 1,000 ft of Sheep Mountain, in sec. 24, T. 15 N., R. 18 W., and in sec. 30, T. 14 N., R. 17 W., Missoula Co., MT. Origin of name not stated, but probably named from Sheep Mountain (Clapp and Deiss, 1931).
AAPG geologic province:
Northern Rocky Mountain region
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 ([ ]).