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Geologic Unit: Franklin
Map showing publication footprint
  • Usage in publication:
    • Franklin gneiss
  • Modifications:
    • Informally named
  • Dominant lithology:
    • Gneiss
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Seal, T.L., and Kish, S.A., 1990, The geology of the Dadeville Complex of the western Georgia and eastern Alabama Inner Piedmont; initial petrographic, geochemical, and geochronological results, IN Steltenpohl, M.G., and others, eds., Geology of the southern Inner Piedmont, Alabama and southwest Georgia; Field trip no. 7: Geological Society of America, Southeastern Section, Guidebook for Field Trips, 39th annual meeting, Tuscaloosa, AL, April 5-6,1990, p. 65-77.


Summary:

Largest intrusive body in the study area is a granitic gneiss, informally named the Franklin gneiss. Outcrops abundant in Heard Co., GA, near town of Franklin. Unit is a light-gray, medium- to coarse-grained gneiss with granoblastic to blastoporphyritic texture. Granite pluton of batholith scale is metamorphosed and deformed. Exceeds 135 sq mi in extent. Rb-Sr whole-rock age of 462+/-4 Ma (Middle Ordovician) on Franklin provides minimum age constraint on Dadeville Complex, which it intrudes.

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

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