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Map showing publication footprint
  • Usage in publication:
    • Miguelito Member
  • Modifications:
    • Named
    • Biostratigraphic dating
  • Dominant lithology:
    • Claystone
    • Siltstone
    • Diatomite
    • Sandstone
  • AAPG geologic province:
    • California Coast Ranges province
Publication:

Hall, C.A., Jr., 1973, Geology of the Arroyo Grande 15' quadrangle, San Luis Obispo County, California: California Division of Mines and Geology Map Sheet, 24, 1 sheet, 8 p., scale 1:48,000


Summary:

Named as second from lowermost member (of five) of Pismo Formation after San Miguelito Land Grant. Type section is on north limb of Pismo syncline on San Luis Obispo Creek, approximately 1 mi north of Squire Canyon, Pismo Beach 7.5' quad, San Luis Obispo Co., CA. Consists of brown-gray or greenish-gray claystone or siltstone with some diatomite and bituminous sandstone lenses. Is 2250 feet thick. Disconformably overlies Monterey Formation; interfingers with or overlies Edna Member (new) (Pismo Formation); underlies Gragg or Squire Member (both new of Pismo Formation). Based on megafossils age is late Miocene and early Pliocene.

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


Map showing publication footprint
  • Usage in publication:
    • Miguelito Member*
  • Modifications:
    • Adopted
  • AAPG geologic province:
    • California Coast Ranges province
Publication:

Hall, C.A., Jr., 1973, Geologic map of the Morro Bay South and Port San Luis quadrangles, San Luis Obispo County, California: U.S. Geological Survey Miscellaneous Field Studies Map, MF-511, 1 sheet, scale 1:24,000


Summary:

Miguelito Member of Pismo Formation of Hall (1973) is adopted. Shown on geologic map of Morro Bay South and port San Luis 7.5' quads, San Luis Obispo Co., CA, undivided with Edna Member of Pismo Formation. Four lithologies are shown separately. Age is Miocene and Pliocene based on fossils, some collected in adjoining Arroyo Grande 15' quad (Hall, 1973).

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


Map showing publication footprint
  • Usage in publication:
    • Miguelito Member*
  • Modifications:
    • Age modified
    • Biostratigraphic dating
  • AAPG geologic province:
    • California Coast Ranges province
Publication:

Keller, M.A., 1992, Field guide to the upper Miocene siliceous coastal sequence of Montana de Oro State Park, California, IN Schwalbach, J.R., and Bohacs, K.M., eds., Sequence stratigraphy in fine-grained rocks; examples from the Monterey Formation: Society of Economic Paleontologists and Mineralogists, Pacific Section, Field Trip Guidebook, book 70, p. 67-80.


Summary:

Unit age given as late Miocene (only) in report area based on diatom and silicoflagellate assemblages from the unit.

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


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Asterisk (*) indicates published by U.S. Geological Survey authors.

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