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Map showing publication footprint
  • Usage in publication:
    • Bald Hills formation
  • Modifications:
    • Named
    • Biostratigraphic dating
  • Dominant lithology:
    • Conglomerate
    • Sandstone
    • Mudstone
  • AAPG geologic province:
    • Sacramento basin
Publication:

Murphy, M.A., and Rodda, P.U., 1960, Mollusca of the Cretaceous Bald Hills formation of California: Journal of Paleontology, v. 34, no. 5, p. 835-858.


Summary:

Bald Hills formation. Conglomerate, sandstone, and mudstone unit cropping out in northeast quarter of Ono 15-min quadrangle. Thickness 1,870 feet at type. Conformably overlies Ono formation; conformably underlies unnamed Upper Cretaceous mudstone unit. Age ranges from late Albian to late Cenomanian, based on molluscan fauna. Report includes list and descriptions of fauna.
Type section: in Bald Hills, along Crow Creek, in secs. 25, 26, and 31, T. 30 N., R. 7 W., Ono 15-min quadrangle, Shasta Co., CA. Named from Bald Hills.

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


Map showing publication footprint
  • Usage in publication:
    • Bald Hills member
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Sacramento basin
Publication:

Murphy, M.A., Peterson, G.L., and Rodda, P.U., 1964, Revision of Cretaceous lithostratigraphic nomenclature, northwest Sacramento Valley, California: American Association of Petroleum Geologists Bulletin, v. 48, no. 4, p. 496-502. [Available online, with subscription, from AAPG archives: http://www.aapg.org/datasystems or http://search.datapages.com]


Summary:

Bald Hills Formation of Murphy and Rodda (1960) is reduced to Bald Hills Member of Budden Canyon Formation (new) on basis of mapping south of Roaring River in Ono 15-min quadrangle. Underlies Gas Point Member; overlies Chickabally Mudstone Member (both new and of Budden Canyon Formation). Cretaceous fossils are abundant. Shown on geologic sketch map of Ono and Chanchelulla Peak 15-min quadrangles.

Source: Modified from 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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