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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Steamboat Rock Basalt*
  • Modifications:
    • Named
  • Dominant lithology:
    • Basalt
  • AAPG geologic province:
    • Snake River basin
Publication:

Howard, K.A., and Shervais, J.W., 1973, Geologic map of Smith Prairie, Elmore County, Idaho: U.S. Geological Survey Miscellaneous Investigations Series Map, I-818, 1 sheet, scale 1:24,000


Summary:

Unit is named the Steamboat Rock Basalt. Consists of medium- to dark-gray basalt. Maximum thickness is 180 m. Unconformably overlies unnamed pre-Pliocene rocks; unconformably underlies unnamed Pliocene or Pleistocene gravel or the Smith Prairie Basalt. Age is Pliocene or Pleistocene. (B1520)

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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