- Usage in publication:
-
- Sitgreaves tuff*
- Modifications:
-
- Named
- Dominant lithology:
-
- Tuff
- AAPG geologic province:
-
- Plateau sedimentary province
Summary:
Named for Sitgreaves Pass, sec 12, T19N, R20W, Mohave Co, AZ in the Plateau sedimentary province. No type locality designated. Rests partly on Gold Road latite (new), partly on Flag Spring trachyte (new), and partly on Meadow Creek trachyte (new). Deposited on erosional surface. Forms conspicuous bluffs. Composed of cream-colored, pumiceous tuff in thick beds. Is of variable thickness. Has a maximum thickness of 200 to 300 ft. Mapped (geologic map) in vicinity of Sitgreaves Pass, and east and north of Cottonwood Canyon, Ts19 and 20N, Rs19 and 20W. Tertiary age.
Source: GNU records (USGS DDS-6; Denver GNULEX).
- Usage in publication:
-
- Sitgreaves Tuff*
- Modifications:
-
- Overview
- AAPG geologic province:
-
- Plateau sedimentary province
Summary:
Is a volcaniclastic unit that is temporally equivalent to the Antelope Rhyolite, Cottonwood Formation (redescribed), Flag Spring Quartz Latite (redescribed), and Meadow Creek Quartz Latite (redescribed). Is younger than Gold Road Dacite (redescribed) and older than some unconformably overlying unnamed Tertiary basalt. Contains conglomerate and air-fall tuff, and many lithic fragments from the Antelope, Cottonwood, Flag Spring, and Meadow Creek. Separately mapped (geologic maps) only at northeast corner of area, Mohave Co, AZ in the Plateau sedimentary province. Of Miocene 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 ([ ]).