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National Geologic Map Database

Geologic Unit: Harrell

Usage:

Harrell Formation (PA*)
Harrell Shale (MD*,WV*)
Harrell Shale of Susquehanna Group (PA*)
Harrell Shale Member of Fort Littleton Formation of Susquehanna Group (PA)


Subunits:

Burket Shale Member (PA*,MD*,WV*) (at base).


Geologic age:

Late Devonian (Frasnian)*


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

Harrell Station on Petersburg branch of the Pennsylvania RR, about midway between Hollidaysburg and Williamsburg, Blair Co., central PA (Butts, 1918).


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 ([ ]).