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Geologic Unit: Yadkin

Yadkin Formation (NC)
Yadkin Formation of Albemarle Group (NC*)
Yadkin Graywacke of Albemarle Group (NC)

Proterozoic, Late
Cambrian, Early(?)*
Geologic Province:
Piedmont-Blue Ridge province*

Areal Extent:

Type Locality:
Roadcut on west side of NC Highway 8 about 100 ft south of where Riles Creek crosses the road, 1 mi north of intersection with U.S. Highway 52, Stanly Co., central NC (Conley and Bain, 1965).

Unit Name History:
Named Yadkin graywacke (Conley and Bain, 1965).
Revised to member of Millingport Formation; Age modified (Stromquist and Sundelius, 1969).
Age modified (Butler and Ragland, 1969; Randazzo, 1972; Stromquist and Sundelius, 1975; Seiders and Wright, 1977; Kish and Black, 1982).
Revised to Yadkin Formation; Age modified (Milton, 1984).
NC State Geol. Map usage (Brown and others, 1985).
Continued use of Yadkin graywacke (Gibson and Huntsman, 1988).
Isotopic dating (Rankin and others, 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