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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Sunshine Ranch member
  • Modifications:
    • Named
    • Biostratigraphic dating
  • Dominant lithology:
    • Sandstone
    • Mudstone
    • Gravel
  • AAPG geologic province:
    • Los Angeles basin
Publication:

Oakeshott, G.B., 1950, Geology of the Placerita oil field, Los Angeles County, California: California Journal of Mines and Geology, v. 46, no. 1, p. 43-79, (incl. geologic map)


Summary:

Unit is named the Sunshine Ranch member of the Pico formation. Consists of pebbly to cobbly cross-bedded sandstone, mudstone, gravel, and concretionary limestone. Thickness along the Sierra Highway is approximately 1,300 feet. At this location unit unconformably (angular) overlies the Mint Canyon formation; disconformably(?) underlies the Saugus formation. Age is late Pliocene based on fossils and stratigraphic position.

Source: GNU records (USGS DDS-6; Menlo GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Sunshine Ranch member*
  • Modifications:
    • Adopted
  • AAPG geologic province:
    • Los Angeles basin
Publication:

Winterer, E.L., and Durham, D.L., 1958, Geologic map of a part of the Ventura basin, Los Angeles County, California: U.S. Geological Survey Oil and Gas Investigations Map, OM-196, 1 sheet, scale 1:24,000


Summary:

Sunshine Ranch member of the Pico formation (Oakeshott, 1950) is adopted as the Sunshine Ranch member of the Saugus formation. Age is Pliocene.

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 ([ ]).

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