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National Geologic Map Database
Geologic Unit: Pratt Ferry
Map showing publication footprint
  • Usage in publication:
    • Pratt Ferry formation
  • Modifications:
    • Named
  • Dominant lithology:
    • Calcarenite
    • Limestone
  • 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:

Name Pratt Ferry formation proposed for somewhat bituminous calcarenite occurring in layers up to 4 in. or more in thickness in central AL. Total thickness about 8 ft. Underlies black shale of Columbiana formation (new); overlies limestone mapped as Lenoir, but which is faunally similar to Little Oak formation. Name attributed to B.N. Cooper and G.A. Cooper. Age is Middle Ordovician (Mohawkian).

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


Map showing publication footprint
  • Usage in publication:
    • Pratt Ferry beds
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Appalachian basin
Publication:

Drahovzal, J.A., and Neathery, T.L., 1971, Middle and Upper Ordovician stratigraphy of the Alabama Appalachians, IN Drahovzal, J.A., and Neathery, T.L., eds., The Middle and Upper Ordovician of the Alabama Appalachians: Alabama Geological Society Annual Field Trip Guidebook, December, 1971, no. 9, p. 1-62.


Summary:

Pratt Ferry reduced in rank and status because of its limited thickness and areal extent. Named used informally here for highly fossiliferous limestone at base of Athens Formation in Bibb Co., AL. Thickness is 10 ft. Age is Middle Ordovician.

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 ([ ]).