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National Geologic Map Database
Geologic Unit: Wassum
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Map showing publication footprint
  • Usage in publication:
    • Wassum formation
  • Modifications:
    • Named
  • Dominant lithology:
    • Limestone
    • Shale
  • AAPG geologic province:
    • Appalachian basin
Publication:

Cooper, G.A., 1956, Chazyan and related brachiopods [U.S.-Canada]: Smithsonian Miscellaneous Collections, v. 127, pt. 1, 1245 p.


Summary:

Named the Wassum formation for Wassum, Smyth Co., VA. Consists of calcarenites and buff crumbly shales. Total thickness is 150 feet. Unit overlies the Chatham Hill formation and underlies the Bays Formation. The Wassum is of Middle Ordovician (Mohawkian) age.

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


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).