- Usage in publication:
-
- Rincon Valley Granite*
- Modifications:
-
- Geochronologic dating
- AAPG geologic province:
-
- Southwestern Basin-and-Range region
Summary:
Sample collected from Rincon Valley Granite in the Rincon Mountains, AZ, Lat. 32 deg. 06 min. N., Long. 110 deg. 26 min. W. Age is Precambrian. Calculated K-Ar age on biotite 1,540 +/-60 Ma. Other reported ages: K-Ar age on biotite 1,450 +/-50 Ma; K-Ar age on hornblende 1,560 +/-100 Ma.
Source: Modified from GNU records (USGS DDS-6; Denver GNULEX).
- Usage in publication:
-
- Rincon Valley Granodiorite*
- Modifications:
-
- First used
- Dominant lithology:
-
- Granodiorite
- AAPG geologic province:
-
- Southwestern Basin-and-Range region
Summary:
First published description. First used in an unpublished thesis (Acker, 1958). Type area designated in this report in sec 32 and west part sec 33, T15S, R17E in the Rincon Valley, Pima Co, AZ in the Southwestern Basin-and-Range region. Is widespread in the Rincon Valley quad, east in the Happy Valley quad, and north and northwest into the Bellota Ranch and Reddington quads. Is massive, friable, medium grained, granitic textured. Consists of biotite or biotite and hornblende, quartz, two feldspars, and traces of apatite, sphene, and zircon. Thought to be allochthonous. Probably derived from southwest. Dated; hornblende at 1,560 +/-100 m.y. and biotite at 1,450 +/-60 m.y. Other dates. Precambrian Y age.
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 ([ ]).