- Usage in publication:
-
- Tusas granite
- Modifications:
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- Named
- Dominant lithology:
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- Granite
- Quartz monzonite
- AAPG geologic province:
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- Southern Rocky Mountain region
Summary:
Named. Source of name [Tusas Mountains] and designation of type locality not stated. Is exposed along east side of Petaca area between Jawbone Mountain to Servilleta Plaza and in scattered inliers near Tres Piedras and on Ojo Caliente Mountain, T29N, R7E, and T29N, Rs7 and 8E, Rio Arriba Co, NM in the Southern Rocky Mountain region. Intrudes other Precambrian rocks--Vallecitos rhyolites, Picuris basalts, Ortega quartzite, Petaca schist, Hopewell series. Considered contemporaneous with Dixon granite. Varies in composition and texture. Composed of medium-sized grains, is nonporphyritic, pink, and lacking in ferromagnesian minerals. Includes numerous dark inclusions of Hopewell series (named) north of Tusas Mountain. May vary from monzonite to quartz monzonite. Is younger than Vallecitos rhyolites. Of Proterozoic age. Geologic map.
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 ([ ]).