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Geologic Unit: Alligator Back

Alligator Back Formation (NC*,VA*)
Alligator Back Formation of Lynchburg Group (VA)
Alligator Back Metamorphic Suite (NC,VA)

Proterozoic, Late*
Paleozoic, early*
Geologic Province:
Piedmont-Blue Ridge province*

Areal Extent:

Type Locality:
Exposures on Bluff Mountain (Alligator Back), Lat. 36 deg. 25 min. 02 sec. N., Long. 81 deg. 11 min. 02 sec. W., Whitehead quadrangle, Alleghany Co., northwestern NC. Derivation of name not stated (Rankin and others, 1973).

Unit Name History:
Named (Rankin and others, 1973).
Revised; Areal limits; Overview (Espenshade and others, 1975).
Age modified; Isotopic dating (Fullagar and Dietrich, 1976).
Age modified (Hack, 1982).
Assigned to Lynchburg Group, lithology added (Conley, 1985).
Overview (Brown and others, 1985).
Age modified to Late Proterozoic and (or) early Paleozoic; Areal limits; Overview (Goldsmith and others, 1988).
Renamed Metamorphic Suite; Age modified (Raymond and others, 1989).
Revised (Rader and Evans, 1993).

Note: If you need more information, please contact Nancy Stamm (
Asterisks (*) indicate usage by the U.S. Geological Survey. Other usages by state geological surveys.

"No current usage" implies that a name has been abandoned or that it has fallen into disuse. Former usage and, if known, replacement name given in parentheses ().

Slashes (/) indicate unit name usage violates the 1983 North American Stratigraphic Code. This violation may be explained within brackets ([ ]).

U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA
Database project personnel
Last modified: 15-Jan-2013