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National Geologic Map Database

Geologic Unit: Bonner

Usage:

Bonner Formation of Missoula Group of Belt Supergroup (ID*,MT*,WA?)
Bonner Quartzite of Missoula Group of Belt Supergroup (MT*)


Geologic age:

Middle Proterozoic*


Type section, locality, area and/or origin of name:

Type locality: in Lolo National Forest, Bonner quadrangle, Missoula Co., western MT. Notable exposures just above town of Bonner, on both sides of Blackfoot River, [in sec. 15, T. 13 N., R. 18 W., southwestern corner Blue Point 7.5-min quadrangle, Missoula Co., western MT] (Nelson and Dobell, 1961).
Reference section: Camp Creek section, along crest of the ridge parallel to and northwest of Camp Creek, in secs. 22, 28, and 33, T. 20 N., R. 12 W., Lewis and Clark Range, Powell Co., MT (McGill and Sommers, 1967).


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