- Usage in publication:
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- Zuma Volcanics*
- Modifications:
-
- Original reference
- Dominant lithology:
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- Basalt
- Breccia
- Tuff
- AAPG geologic province:
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- Transverse Ranges province
Summary:
Pg. E27-E28. Zuma Volcanics. Consists of basaltic and andesitic flows, breccias, and tuffs with minor volcanic sediment and interbeds of mudstone and siltstone. Thickness ranges from 800 to 1,000 m. Exposed in elongate fault slices. Base is nowhere exposed; inferred to unconformably overlie Catalina Schist. Intertongues with Trancas Formation (new). Intertongues with and underlies Monterey Shale. Age is early and middle Miocene.
Type locality: exposures on west side of Zuma Canyon about 4 km north of Point Dume, Santa Monica Mountains, south-central Point Dume quadrangle, Los Angeles Co., southern CA.
Source: US geologic names lexicon (USGS Bull. 1564, p. 190-191); GNU records (USGS DDS-6; Menlo 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 ([ ]).