U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database

Geologic Unit: Dolores

Usage:

Dolores Formation (CO*)


Geologic age:

Triassic, Late*


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

Named from typical exposures of the fossil-bearing strata in valley of Dolores River, at present best known in Rico quadrangle, southwestern CO (Cross and Purington, 1899).


AAPG geologic province:

Paradox basin*
San Juan Mountains province*
San Juan 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 ([ ]).