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Map showing publication footprint
  • Usage in publication:
    • Tierra Redonda Formation*
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
    • Conglomerate
  • AAPG geologic province:
    • California Coast Ranges province
Publication:

Durham, D.L., 1968, Geology of the Tierra Redonda Mountain and Bradley quadrangles, Monterey and San Luis Obispo Counties, California: U.S. Geological Survey Bulletin, 1255, 60 p., (incl. geologic map, scale 1:24,000) [http://ngmdb.usgs.gov/Prodesc/proddesc_257.htm]


Summary:

Unit is named the Tierra Redonda Formation. Consists of fine- to coarse-grained, thick-bedded, friable to well-cemented, white and yellowish-gray sandstone (calcareous in the lower part) and boulder conglomerate. Thickness is 1650 ft at type. Conformably overlies the Vaqueros Formation; conformably underlies the Sandholdt Member of the Monterey Shale. Age is early and middle Miocene. (B1520)

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


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

Durham, D.L., 1974, Geology of the southern Salinas Valley area, California: U.S. Geological Survey Professional Paper, 819, 111 p., (incl. geologic map, scale 1:125,000) [http://ngmdb.usgs.gov/Prodesc/proddesc_259.htm]


Summary:

Age of the Tierra Redonda Formation is modified from early and middle Miocene to: middle Miocene based on fossils [mollusks].

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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