Usage:
Hamilton Group (MD*,NY*,OH*,PA*,VA*,WV*)
Hamilton Formation (NJ,PA*,VA*,WV*)
Hamilton Shale (NY,PA*)
Hamilton Shale Member of Romney Formation (MD)
Subunits:
(ascending) Marcellus Shale (MD*,NY*,OH*,PA*,VA*,WV*), Skaneateles Shale (MD*,NY*,OH*,PA*,WV*), Ludlowville Shale (MD*,NY*,OH*,WV*), and Moscow Shale (MD*,NY*,PA*,WV*); Mount Marion Formation (NY*)
Geologic age:
Middle Devonian*
Type section, locality, area and/or origin of name:
West Hamilton and Hamilton, Madison Co., NY (Vanuxem, 1840).
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 ([ ]).