- Usage in publication:
-
- Eagle Peak syenite*
- Modifications:
-
- Original reference
- Dominant lithology:
-
- Syenite
- AAPG geologic province:
-
- Permian basin
Summary:
Pg. 38, pl. 1. Eagle Peak syenite. Proposed for brownish-gray, medium-grained rock with large phenocrysts of feldspar, chiefly orthoclase, which occurs in central and highest part of Eagle Mountains and is exposed on Eagle Peak. Much of rock has been altered to "soda syenite". Crops out as roughly elliptical-shaped body, with, in the main, almost vertical contacts with surrounding rhyolite. Age is Tertiary.
Altered syenite is well exposed on summit of Eagle Peak; unaltered syenite is well exposed on flanks of Eagle Peak and in Wind Canyon 1.5 mi southeast of Eagle Peak, Hudspeth Co., southwestern TX.
Source: US geologic names lexicon (USGS Bull. 1200, p. 1197).
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 ([ ]).