Usage:
Emerson Formation (MT*)
Subunits:
Zortman Member (MT).
Geologic age:
Cambrian, Middle*
Cambrian, Late*
Ordovician, Early*
Type section, locality, area and/or origin of name:
In SW/4 sec. 20, T. 26 N., R. 25 E., at or near mouth of Emerson Gulch on Lodgepole Creek, Phillips Co., MT (Knechtel, 1956).
AAPG geologic province:
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 ([ ]).