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Map showing publication footprint
  • Usage in publication:
    • Norcross Gneiss*
  • Modifications:
    • Named
  • Dominant lithology:
    • Gneiss
    • Amphibolite
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Higgins, M.W., and Atkins, R.L., 1981, The stratigraphy of the Piedmont southeast of the Brevard zone in the Atlanta, Georgia, area, IN Wigley, P.B., ed., Latest thinking on the stratigraphy of selected areas in Georgia; Volume 1: Georgia Geologic Survey Information Circular, no. 54-A, p. 3-40.


Summary:

The Norcross Gneiss of the Atlanta Group, here named in the Newnan-Tucker synform near Atlanta, GA, consists of well-foliated gray, epidote-biotite-muscovite-plagioclase gneiss with pods and lenses of amphibolite. It is in sharp contact and correlative with the Wolf Creek Formation to the southwest; it is gradational and conformable with the overlying Clairmont Formation. 2,000 m thick. Age is Late Proterozoic and (or) early Paleozoic.

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


Map showing publication footprint
  • Usage in publication:
    • Norcross Gneiss*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Higgins, M.W., Atkins, R.L., Crawford, T.J., Crawford, R.F., III, Brooks, Rebekah, and Cook, R.B., Jr., 1988, The structure, stratigraphy, tectonostratigraphy, and evolution of the southernmost part of the Appalachian Orogen, Georgia and Alabama: U.S. Geological Survey Professional Paper, 1475, 173 p., (incl. geologic map, scale 1:500,000)


Summary:

The Norcross Gneiss is removed from the Atlanta Group, here abandoned. It is a granitic sill in the Clairmont thrust sheet which separates the main mass of the Clairmont melange from the lower part, which was formerly named the Inman Yard Formation but is now known to be part of the Clairmont Formation. The Norcross is interpreted to be a remnant of a subduction melange associated with the volcanic arc in which rocks in overlying thrust sheets formed. Age is Silurian(?).

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


Map showing publication footprint
  • Usage in publication:
    • Norcross Gneiss†
  • Modifications:
    • Abandoned
  • AAPG geologic province:
    • Piedmont-Blue Ridge province
Publication:

Crawford, T.J., Higgins, M.W., Crawford, R.F., Atkins, R.L., Medlin, J.H., and Stern, T.W., 1999, Revision of stratigraphic nomenclature in the Atlanta, Athens, and Cartersville 30' x 60' quadrangles, Georgia: Georgia Geologic Survey Bulletin, no. 130, 45 p.


Summary:

Recent mapping has shown Norcross Gneiss to be a facies of Lithonia Gneiss. Because Lithonia is a well-established name and takes precedence over Norcross, Norcross Gneiss is herein abandoned.

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


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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 ([ ]).