Perkasie Member of Passaic Formation (NJ*,PA)
Perkasie Member of Brunswick Group (PA*)
Perkasie Member of Brunswick Formation (NJ,PA)
Triassic, Late*
Norian
Not designated. Occurs near the Perkasie tunnel, Bucks Co., PA (Lyman, 1895).
Piedmont-Blue Ridge province*
Newark 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 ([ ]).