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  • Usage in publication:
    • Hunter Valley cherts
  • Modifications:
    • First used
  • Dominant lithology:
    • Chert
    • Tuff
  • AAPG geologic province:
    • Sierra Nevada province
Publication:

Taliaferro, N.L., 1933, Bedrock complex of the Sierra Nevada, west of the southern end of the Mother Lode [abs.]: Geological Society of America Bulletin, 45th annual meeting, Cambridge, MA, December 28-30, 1932, v. 44, no. 1, p. 149.


Summary:

On Merced River and southward into Indian Gulch 15-min quadrangle, Mariposa County, California, Hunter Valley cherts and tuffs, 1,500 feet thick, included in Tuolumne [later Amador] group. Underlie Penon Blanco agglomerates (new). Age is probably early Mesozoic.

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


  • Usage in publication:
    • Hunter Valley cherts
  • Modifications:
    • Named
  • Dominant lithology:
    • Chert
    • Slate
    • Tuff
  • AAPG geologic province:
    • Sierra Nevada province
Publication:

Taliaferro, N.L., 1943, Manganese deposits of the Sierra Nevada, their genesis and metamorphism: California Division of Mines Bulletin, no. 125, p. 277-332.


Summary:

Pg. 283, 303-323. Hunter Valley cherts. Assigned to Amador group. Consist of red, chocolate, gray, green, and black radiolarian chert, both massive and thin-bedded with partings of red, lilac, purple, chocolate, gray-green, and black slates and tuffaceous slates; schistose green tuffs and thin flows; impure cherts and siliceous mudstones near top of section. In Merced River section, Hunter Valley cherts overlie pillow basalts and underlie Penon Blanco volcanics. Thickness 950 feet. Equivalent to part of Cosumnes formation. Age of Amador group is believed to be late Middle to early Late Jurassic.
Occurs along Merced River in southern type section of Amador group. [Name probably derived from Hunter Valley in eastern part of Coulterville 15-min quadrangle, Mariposa Co., CA.]
[Misprint: GNU records (USGS DDS-6; Menlo GNULEX, Sept. 20, 1988) state thickness is 90 feet; should be 950 feet.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 1842); GNU records (USGS DDS-6; Menlo GNULEX).


  • Usage in publication:
    • Hunter Valley cherts
  • Modifications:
    • Not used
  • AAPG geologic province:
    • Sierra Nevada province
Publication:

Clark, L.D., 1964, Stratigraphy and structure of part of the western Sierra Nevada metamorphic belt, California: U.S. Geological Survey Professional Paper, 410, 70 p., (incl. geologic maps, scale 1:316,800 and 1:62,500), Prepared in cooperation with California Div. Mines Geol


Summary:

The five formations of the Amador Group (Taliaferro, 1943, California Div. Mines Bull., no. 125) in Merced River area are not used in this report [except for Penon Blanco volcanics].
[Author does not capitalize rank terms; however, units are considered formal.]

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


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