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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Black Girl limestone
  • Modifications:
    • Areal extent
  • Dominant lithology:
    • Limestone
  • AAPG geologic province:
    • San Juan Mountains province
Publication:

Irving, J.D., 1905, Ore deposits of the Ouray district, Colorado, with a note on the geology by Ernest Howe, IN Contributions to economic geology, 1904: U.S. Geological Survey Bulletin, 260, p. 50-77.


Summary:

Pg. 56. [Black Girl and Pony Express limestone is shown as basal bed of McElmo formation in section of Gold Hill, Ouray district, southwestern Colorado. Age is Late Jurassic.]

Source: US geologic names lexicon (USGS Bull. 896, p. 201, Pony Express entry p. 1699).


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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