Usage:
Potlatch Anhydrite (MT*-local)
Potlatch Formation of Three Forks Group (MT-local)
Recognized locally in subsurface of Sweetgrass arch, northwestern MT.
Geologic age:
Late Devonian*
Type section, locality, area and/or origin of name:
Named from fact that complete section (subsurface) is shown in cuttings of the Potlatch Adams No. 1 well, in sec. 21, T. 34 N., R. 1 W., Tooele Co., northwestern MT (Sandberg and Hammond, 1958).
AAPG geologic province:
Sweetgrass arch*
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 ([ ]).