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Map showing publication footprint
  • Usage in publication:
    • Agate Creek Formation
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Tuff
  • AAPG geologic province:
    • South Park basin
Publication:

De Voto, R.H., 1964, Stratigraphy and structure of Tertiary rocks in southwestern South Park: The Mountain Geologist, v. 1, no. 3, p. 117-126.


Summary:

Pg. 119-121. Agate Creek Formation. Welded trachytic, crystal vitric tuff, consisting of a lower black lenticular zone of dense welding and an upper reddish zone of partial welding. Thickness 11 feet at type locality; 600 feet in vicinity of Mushroom Gulch syncline. Unconformably overlies Denver(?) Formation. Underlies and is interbedded locally with Antero Formation. Age is early Oligocene.
Type exposures: on south flank of syncline near Agate Creek, in NE/4 SE/4 sec. 7 and NW/4 SW/4 sec. 8, T. 14 S., R. 75 W., Antero Reservoir quadrangle, southwestern South Park, [Park Co.], central CO.

Source: US geologic names lexicon (USGS Bull. 1350, p. 7-8).


Map showing publication footprint
  • Usage in publication:
    • Agate Creek Formation*
  • Modifications:
    • Not used
Publication:

Epis, R.C., and Chapin, C.E., 1974, Stratigraphic nomenclature of the Thirtynine Mile volcanic field, central Colorado, IN Contributions to stratigraphy: U.S. Geological Survey Bulletin, 1395-C, p. C1-C23.


Summary:

Not used in Denver basin. Replaced by name Wall Creek Tuff.

Source: GNU records (USGS DDS-6; Denver 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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