- Usage in publication:
-
- Clifton Forge sandstone member*
- Modifications:
-
- Named
- Dominant lithology:
-
- Sandstone
- AAPG geologic province:
-
- Appalachian basin
Summary:
Clifton Forge sandstone member, middle member of Keyser limestone is named in west-central VA. Consists of calcareous sandstones and shaly sandstones with some arenaceous shale at Clifton Forge, Hot Springs, Gala, and other places in western VA. Thickness ranges from 66 to 102 ft; 66 ft at Clifton Forge). Intertongues with and finally replaces the upper limestone and Big Mountain shale members of Keyser. Overlies lower member of Keyser. Age is Early Devonian.
Source: GNU records (USGS DDS-6; Reston GNULEX).
- Usage in publication:
-
- Clifton Forge Sandstone Member*
- Modifications:
-
- Age modified
- AAPG geologic province:
-
- Appalachian basin
Summary:
Conodont data and extrapolation from regional lithofacies relationships indicate that the Silurian-Devonian boundary lies within the uppermost Keyser Limestone (in the upper limestone member in west-central VA and east-central WV, and in the La Vale Member in northeast WV and central PA [and in MD by implication]). Therefore, Byers Island, Jersey Shore, Big Mountain Shale, and Clifton Forge Sandstone Members considered entirely Late Silurian.
Source: GNU records (USGS DDS-6; Reston GNULEX).
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 ([ ]).