Usage:
Loyalhanna Formation (PA)
Loyalhanna Limestone (MD*,PA*)
Loyalhanna Limestone Member of Greenbrier Formation (MD*)
Loyalhanna Limestone Member of Mauch Chunk Formation (PA)
Loyalhanna Member of Greenbrier Limestone (WV,MD)
Geologic age:
Middle Mississippian (Visean; early Chesterian)*
Type section, locality, area and/or origin of name:
Named from exposures in gorge in which Loyalhanna Creek flows across Chestnut Ridge in Westmoreland Co., PA (Butts, 1904).
AAPG geologic province:
Appalachian basin*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"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 conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).