- Usage in publication:
-
- Squaw Gulch Granite*
- Modifications:
-
- Named
- Geochronologic dating
- Dominant lithology:
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- Granite
- AAPG geologic province:
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- Basin-and-Range province
Summary:
Named. Type area is along middle reaches of Squaw Gulch, Santa Rita Mountains, Mount Wrightson quad, Santa Cruz Co, AZ. Occurs in much of south-central part of Santa Rita Mountains. Is a coarse-grained and pink granite that forms a large stock. Is myrmekitic and in part granophyric granite to sodic quartz monzonite. Intrudes rocks as young as Triassic Piper Gulch Monzonite. Is unconformably overlain by Early Cretaceous Temporal Formation. Biotite from unit has K-Ar age of 145 +/-4 Ma. Zr was dated by Pb-alpha method as 160 +/-20 Ma and 161 +/-20 Ma. Assigned to the Jurassic.
[NOTE: In accordance with Department of Interior's Secretarial Order 3404, discontinuing use of derogatory term squaw, the Squaw Gulch Granite is in process of being formally renamed Santa Rita Gulch Granite (RESERVED). The geographic feature Squaw Gulch, from which the geologic name was taken (this report), was renamed Santa Rita Gulch by U.S. Board on Geographic Names, September 2022, USGS GNIS FeatureID 638662.]
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 ([ ]).