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National Geologic Map Database

Geologic Unit: Molas

Usage:

Molas Formation (AZ*,CO*,NM*,UT*)


Subunits:

Coalbank Hill Member (CO*).


Geologic age:

Early to Middle Pennsylvanian (Atokan to Morrowan)*


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

Named from Molas Lake, in San Juan Mountains on Durango-Silverton Highway, Needle Mountains quadrangle, [San Juan Co.], southwestern CO (Cross and Howe, 1905).
Typical section measured on north side of Canyon Creek below Box Canyon, Ouray Co., CO (Burbank, 1930).


AAPG geologic province:

Black Mesa basin*
Eagle basin*
Paradox basin*
Piceance basin*
Plateau sedimentary province*
San Juan basin*
San Juan Mountains province*


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 ([ ]).