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Geologic Units: Cortina
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Map showing publication footprint
  • Usage in publication:
    • Cortina Formation
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
    • Siltstone
    • Mudstone
  • AAPG geologic province:
    • Sacramento basin
Publication:

Ingersoll, R.V., Rich, E.E., and Dickinson, W.R., 1977, Field guide; Great Valley Sequence, Sacramento Valley; [Field trip no. 8]: Geological Society of America, Cordilleran Section, Guidebook for Field Trips, 73rd annual meeting, Sacramento, CA, April 5-7, 1977, 72 p.


Summary:

Type section; exposures on Cortina Ridge, Wilbur Springs quad, Colusa Co, CA. Contains Venado Sandstone Member at base and Sites Sandstone Member. Consists of olive and gray sandstone, siltstone, and mudstone. Thickness is 2,900 m. Is thin- to thick-bedded; coarse-grained; mixed plutonic and volcanic detritus deposited in deep-marine trough. Conformably overlies or intertongues with Boxer Formation; underlies Rumsey Formation. Is Late Cretaceous 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.

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