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National Geologic Map Database

Geologic Unit: Emerson

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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).