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Map showing publication footprint
  • Usage in publication:
    • San Miguel volcanics
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
    • Siltstone
    • Ash
    • Tuff
    • Basalt
    • Porphyry
  • AAPG geologic province:
    • Santa Maria basin
Publication:

Weaver, D.W., and Doerner, D.P., 1969, Mid-Tertiary stratigraphy, San Miguel Island, IN Weaver, D.W., Doerner, D.P., and Nolf, Bruce, eds., Geology of the northern Channel Islands, southern California borderland: American Association of Petroleum Geologists, Pacific Section, Field Trip Guidebook, [no. 12], p. 80-84, (incl. geologic map, scale approx. 1:63,000)


Summary:

Named for occurrence on eastern San Miguel Island, Channel Islands, southwestern CA. Extends as far east as Santa Rosa Island. Mapped by Bremner (1933) as basalt member of his Temblor Formation. Consists of dark colored volcanic sandstone, siltstone, basaltic ash, tuff, thin flows of basalt, and dacite porphyry. Divided into lower and upper members on map of San Miguel Islands. Is at least 1520 ft thick. Gradationally overlies Rincon Formation. Underlies Monterey Formation. Oligocene and Miocene foraminifers are listed. Age given as Oligocene on map legend.

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


Map showing publication footprint
  • Usage in publication:
    • San Miguel Volcanics*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • Santa Maria basin
Publication:

Vedder, J.G., Beyer, L.A., Junger, Arne, Moore, G.W., Roberts, A.E., Taylor, J.C., and Wagner, H.C., 1974, Preliminary report on the geology of the Continental Borderland of southern California: U.S. Geological Survey Miscellaneous Field Studies Map, MF-624, 9 sheets, 34 p., scale 1:1,000,000, 1:500,000, and 1:268,000


Summary:

San Miguel Volcanics of Weaver and Doerner (1969) listed as middle Miocene age in generalized stratigraphic column of San Miguel Island.

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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