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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Mount Morrison Formation
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Southern Rocky Mountain region
Publication:

Tweto, Ogden, 1977, Nomenclature of Precambrian rocks in Colorado, IN Contributions to stratigraphy: U.S. Geological Survey Bulletin, 1422-D, p. D1-D22.


Summary:

Name applied to the "quartz monzonite gneiss" of Ball (1906) and Lovering and Goddard (1950). Informal terms felsic gneiss or quartzofeldspathic gneiss used on recent maps. Listed with pre-1,700 m.y. (Precambrian X) metamorphic complex. Is in Southern Rocky Mountain region.

Source: GNU records (USGS DDS-6; Denver GNULEX).


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 ([ ]).

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