Johnstown limestone (informal) in Allegheny Formation (PA)
Informal. The rank or lithologic term should not be capitalized.
Pennsylvanian
Johnstown, Cambria Co., PA (Chance, 1880).
Appalachian basin
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
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