- Usage in publication:
-
- Rodeo shale*
- Modifications:
-
- Named
- Dominant lithology:
-
- Shale
- AAPG geologic province:
-
- California Coast Ranges province
Summary:
Named as member of Monterey group for exposures along Rodeo Creek in northwestern part of Concord 15' quad, Contra Costa Co, CA. Consists of bituminous shale, mostly chalky and more or less stained with oxide of iron, but locally cherty. Is about 670 ft thick. Overlies Hambre sandstone (new); underlies Briones sandstone (new) (both of Monterey group). Map legend shows age as Miocene.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
- Usage in publication:
-
- Rodeo shale*
- Modifications:
-
- Age modified
- AAPG geologic province:
-
- California Coast Ranges province
Summary:
Rodeo Shale, uppermost formation (of 6) of Monterey Group is middle Miocene in age.
Source: 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 ([ ]).