- Usage in publication:
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- Arnett Member*
- Modifications:
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- Original reference
- Dominant lithology:
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- Rhyolite
- AAPG geologic province:
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- Basin-and-Range province
Summary:
The Arnett Member of the Sleeping Buffalo Rhyolite (new name), here named, is in the Teapot Mountain quadrangle, Pinal County, Arizona. Consists of light-gray to buff flow-banded, vitrophYric and glomeroporphyritic rhyolite, locally comprising alternating zones of agglomeritic, pumiceous, and dense aphanitic rhyolite. Contains phenocrysts of plagioclase and quartz in a glassy or devitrified groundmass. Conformably overlies older Tertiary tuff; unconformably underlies the Road Runner Rhyolite (new name). Age is Miocene based on potassium-argon ages of 18 to 15.9 Ma of rhyolite in the Mineral Mountain quadrangle to the west. Age is Miocene.
Type locality: exposures in Arnett Creek, in NW/4 sec. 22, T. 2 S., R. 12 E., Teapot Mountain 7.5-min quadrangle, east-central Pinal Co., AZ.
Source: US geologic names lexicon (USGS Bull. 1565, p. 15).
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 ([ ]).