- Usage in publication:
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- Rich Valley formation
- Modifications:
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- Named
- Dominant lithology:
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- Shale
- AAPG geologic province:
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- Appalachian basin
Summary:
Named the Rich Valley formation for Rich Valley, Smyth Co., VA. Consists of black and chocolate shales, which contain graptolites, brachiopods, and trilobites. Thickness ranges from a few feet to 350 feet. Unit overlies the Arline formation and underlies the Chatham Hill formation. Beds herein defined as Rich Valley are the lower and characteristic part of a unit widely identified by Butts (1940) and other workers as Athens shale. Unit corresponds to the lower part of the Liberty Hall black limestone-black shale succession of central western VA. The Rich Valley is of Middle Ordovician age.
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 ([ ]).