Usage:
Keyser Formation (PA*,VA,WV)
Keyser Limestone (MD*,PA*,VA*,WV*)
Keyser Limestone of Helderberg Group (MD*,PA,VA*,WV*)
/Keyser Formation of [†]Cayuga Group (VA)
[†Cayuga, at its type locality, has been abandoned as a lithostratigraphic term, and has been used as a chronostratigraphic term (Cayugan) for some time. To prevent confusion, the use of Cayuga as a lithostratigraphic term should be avoided.]
Subunits:
Big Mountain Shale Member (VA*,WV*), Byers Island Member (PA*,VA*,WV*), Clifton Forge Sandstone Member (VA*,WV*), Jersey Shore Member (PA*,VA*,WV*), LaVale Member (MD*,PA*,VA*,WV*).
Geologic age:
late Silurian (Pridoli) to early Early Devonian (Lochkovian)*
Type section, locality, area and/or origin of name:
Named from exposures at Keyser, [Keyser 7.5-min quadrangle], Mineral Co., northern WV (Ulrich, 1911).
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 ([ ]).