- Usage in publication:
-
- Fox Canyon Formation
- Modifications:
-
- Named
- Dominant lithology:
-
- Porphyry
- Sandstone
- AAPG geologic province:
-
- Permian basin
Summary:
Probably named for Fox Canyon, Jeff Davis Co, TX, Permian basin. Type locality designated in upper Fox Canyon, where the unit consists of multiple flows of trachyte porphyry, and in southeast outcrop area associated sandstone and tuff, with an aggregate thickness of about 120 m. Calcic anorthoclase, augite, and opaques form glomerocrysts in the porphyry. Occurs only in the area between Madera and Adobe Canyons and is here interpreted as an intracaldera trachyte shield volcano. The trachyte porphyry lavas are slabby with rubbly or vesicular tops. Interiors of flows weather to form massive boulders which litter the streams below the outcrop; flows are highly oxidized and weather to deep reddish-brown. Overlies Gomez Tuff; underlies rhyolite lava flows of Adobe Canyon Formation. Geologic map. Chemical analyses. Correlation chart. Of Oligocene 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 ([ ]).