- Usage in publication:
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- Ben Day porphyry
- Modifications:
-
- Original reference
- Dominant lithology:
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- Porphyry
- AAPG geologic province:
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- Permian basin
Summary:
Pg. 344, 347. Ben Day porphyry. Dense grayish porphyry with light-colored glassy-appearing phenocrysts, some of which iridesce like labradorite. Arrangement of phenocrysts in some of the darker porphyries is very regular. Age is early Tertiary.
Type locality not stated. Occurs as sheets, dikes, and necks in Mitre Peak area, which lies across Brewster-Jeff Davis Co. line, roughly 12 mi northwest of Alpine, TX.
Source: US geologic names lexicon (USGS Bull. 1200, p. 299).
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 ([ ]).