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- Usage in publication:
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- Beaver Dam black shale member
- Modifications:
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- Named
- Dominant lithology:
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- Shale
- AAPG geologic province:
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- Appalachian basin
Summary:
Named Beaver Dam black shale member of the Needmore shale for Beaver Dam brook at type locality, Mifflin Co., PA. Unit is a thick black shale near middle of Needmore shale. It is also listed in table 20 as part of the Selinsgrove limestone which overlies the Needmore. Contains a few scattered calcareous concretions, none near base, and thin sandstone partings in lower part. Thickness is 78 feet. The Beaver Dam is of Middle Devonian 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 ([ ]).