Usage:
Dearborn Limestone (MT*)
Geologic age:
Middle Cambrian*
Type section, locality, area and/or origin of name:
Type locality: on north side of valley of North Fork of Dearborn River, in W/2 sec. 6, T. 17 N., R. 7 W., south-central part of Lewis and Clark Range, Lewis and Clark, Co., northwestern MT (Deiss, 1933).
AAPG geologic province:
Montana folded belt*
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 ([ ]).