U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database

Geologic Unit: Dark Ridge

Usage:

Dark Ridge Member of Lee Formation (recognized locally in KY*,TN*,VA*)
Dark Ridge Member of /Bottom Creek formation (informal) of Breathitt Group (KY-local)
Notable exposures in Cumberland Mtn. area.

[Term "Formation" is applied to formal nomenclature (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005).]


Geologic age:

Early Pennsylvanian (Bashkirian; late Namurian to Westphalian; Morrowan)*


Type section, locality, area and/or origin of name:

Type locality [section]: on Skyland Road, near south end of Dark Ridge on north side of Cumberland Gap, Bell Co., southeastern KY, where member occupies poorly exposed interval between massive sandstones of underlying and overlying members (Englund, 1964).


AAPG geologic province:

Appalachian basin*


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 ([ ]).