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National Geologic Map Database

Geologic Unit: Steamboat

Usage:

Steamboat Limestone (MT*)


Geologic age:

Cambrian, Middle*
Albertan


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

Type locality: on eastern and northern sides of Steamboat Mountain, [in T. 18 N., R. 8 W., Steamboat Mountain 7.5-min quadrangle, Lewis and Clark Co.], northwestern MT (Deiss, 1933).
Type locality (emended): crest of Prairie Reef, [in T. 21 N., R. 11 W., Prairie Reef 7.5-min quadrangle, Lewis and Clark Co., northwestern MT], from 54 feet below top of peak northwestward to base of Switchback shale (Deiss, 1938, see also Deiss, 1939).


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