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National Geologic Map Database

Geologic Unit: Clarion

Usage:

Clarion Formation of Allegheny Group (PA*)
Clarion Sandstone Member of Allegheny Formation (MD,WV)
Clarion sandstone (informal, unranked) in Allegheny Group (OH)
Clarion shale (informal, unranked) in Allegheny Group (OH)

For informal, unranked usage, the lithologic term should not be capitalized.


Geologic age:

Middle Pennsylvanian*


Type section, locality, area and/or origin of name:

Named from Clarion, Clarion Co., western PA (Stevenson, 1878).
Reference sections (Williams and Nickelsen, 1958; includes many other sections):
(1) in coal strip mines on western end of large hill, 0.5 mi east of Krebs, northeast rectangle of Glen Richey quadrangle, Clearfield Co., PA; and
(2) in coal strip mines on a small hill, 0.4 mi northeast of mouth of Clearfield Creek, in south-central rectangle of Clearfield quadrangle, Clearfield Co., PA.


AAPG geologic province:

Appalachian basin*


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 ([ ]).