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National Geologic Map Database

Geologic Unit: Forelle

Usage:

Forelle Limestone Member of Goose Egg Formation (CO*,WY*)
Forelle Limestone Member of Lykins Formation (CO*)
Forelle Limestone (CO*,NE*,WY*)


Geologic age:

middle to late Permian (Guadalupian to Lopingian; Roadian to Ochoan)*


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

Named from Forelle RR station, a few mi south of Laramie, [Albany Co.], southeastern WY (Darton, 1908).


AAPG geologic province:

Denver basin*
Green River basin*
Powder River 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 conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).