- Usage in publication:
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- Fannettsburg member
- Modifications:
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- Named
- Dominant lithology:
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- Limestone
- AAPG geologic province:
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- Appalachian basin
Summary:
Named the Fannettsburg member of the Shippensburg formation in south-central PA and western MD for Fannettsburg in Path Valley, Franklin Co., PA. Consists of light to dark gray, medium-grained to coarsely crystalline limestone in platy to massive beds. Shows two intertonguing facies: dark and fine-grained in eastern belts and lighter medium to coarsely crystalline in western belts. Crude vertical zoning also present in western belts; lower part typically medium gray, rather thick-bedded, coarse calcarenite with layers of SOLENOPORA conglomerate, and upper part dark gray, cross-laminated, fine calcarenite in platy beds. Contains four metabentonites in eastern belt. Maximum thickness is 263 feet (39 feet at type locality). Conformably overlies Pinesburg member and conformably underlies Doylesburg member in type section and disconformably underlies Mercersburg formation in eastern belts. The Fannettsburg 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 ( ).
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