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Map showing publication footprint
  • Usage in publication:
    • Santa Cruz Island Schist
  • Modifications:
    • Named
  • Dominant lithology:
    • Schist
  • AAPG geologic province:
    • Santa Maria basin
Publication:

Weaver, D.W., 1969, The pre-Tertiary rocks, 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. 11-13, (incl. geologic map, scale 1:24,000)


Summary:

[Probably named for Santa Cruz Island] Type area designated as exposures in Santa Cruz Island off southern coast of CA. Composed of olive-green to gray-green metamorphosed chloritic schist and greenstones. Texture is fine and even grained. Schistosity is well developed. Is intruded by Alamos Tonalite [new]. Is in fault contact with Willows Diorite (new). Is Paleozoic or lower Mesozoic age based on stratigraphic relations with Willows Diorite with K-Ar age of 145 +/-5 Ma.

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


Map showing publication footprint
  • Usage in publication:
    • Santa Cruz Island Schist
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • Santa Maria basin
Publication:

Hill, D.J., 1976, Geology of the Jurassic basement rocks, Santa Cruz Island, California, and correlation with other basement terranes in California, IN Howell, D.G., ed., Aspects of the geologic history of the California continental borderland: American Association of Petroleum Geologists, Pacific Section, Miscellaneous Publication, California Borderland Symposium, Santa Cruz Island, CA, September 22-26, 1975, no. 24, p. 16-47., Prepared in cooperation with USGS and Univ. California, Channel Islands Field Station


Summary:

Consists chiefly of metavolcanic rocks and less abundant metasedimentary rocks and metamorphosed hypabyssal rocks. May be as much as 5000 ft thick. Formed during volcanism associated with intermittent sedimentation. Intruded by Willows pluton(s) and then by Alamos Pluton. Radiometric ages indicate that plutonic crystallization and metamorphism occurred during Late Jurassic time, and metamorphism may have continued into Cretaceous time.

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


Map showing publication footprint
  • Usage in publication:
    • Santa Cruz Island Schist
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Santa Maria basin
Publication:

Sorensen, Sorena, 1985, Petrologic evidence for Jurassic island-arc-like basement rocks in the southwestern Transverse Ranges and California Continental Borderland: Geological Society of America Bulletin, v. 96, no. 8, p. 997-1006.


Summary:

Unit is sliver of metavolcanic, metaplutonic, and metasedimentary basement rocks of approximately 2 by 15 km juxtaposed against Tertiary Santa Cruz Volcanics along Santa Cruz Island fault and against Willows Plutonic Complex along North Valley Anchorage fault. Intruded by Alamos Pluton which contains zircons yielding U-Pb age of 141 +/-3 Ma, probable lower limit for Santa Cruz Island Schist metamorphism. Detailed petrologic descriptions and comparison with Santa Monica Formation and Willows Plutonic Complex included in study.

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


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