Usage:
Potomac Group (VA*,DC*,MD*,DE*,NJ)
Potomac Formation (VA*,MD*,DE*,NJ*,PA*)
Subunits:
GROUP STATUS: Patuxent Formation (VA*,DC*,MD*,DE*), Arundel Formation (Clay) (DC*,MD*), Patapsco Formation (VA*,DC*,MD*,DE*,NJ).
Geologic age:
Early to early Late Cretaceous (Aptian to Cenomanian)*
Type section, locality, area and/or origin of name:
Not designated.
AAPG geologic province:
Atlantic Coast 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 ([ ]).