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National Geologic Map Database

Geologic Unit: State Bridge

Usage:

State Bridge Formation (CO*)
State Bridge Siltstone (CO)


Subunits:

(alphabetical): Sloane Peak Member (CO*), South Canyon Creek Member (CO*), Yarmony Limestone Member (CO).


Geologic age:

Permian, Early*
Permian, Late*
Triassic, Early*


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

Type section: on south slope of Yarmony Mountain, 0.3 mi north of State Bridge, [in sec. 23, T. 2 S., R. 83 W., State Bridge 7.5-min quadrangle], Eagle Co., CO. Named from State Bridge, Eagle Co., CO (Brill, 1942; see Donner, 1949).


AAPG geologic province:

Eagle basin*
Piceance 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 ([ ]).