Harrell Shale
| Harrell Formation Stratigraphic range: Middle Devonian-Late Devonian |
|
|---|---|
| Type | sedimentary |
| Sub-units | Burket Shale Member |
| Underlies | Brallier Formation and Sonyea Formation |
| Overlies | Mahantango Formation, Millboro Shale, and Tully Limestone |
| Lithology | |
| Primary | shale, sandstone |
| Location | |
| Region | Appalachian Mountains |
| Country | United States |
| Type section | |
| Named by | Charles Butts, 1918 |
The Devonian Harrell Formation is a mapped bedrock unit in Pennsylvania, Maryland, West Virginia, and Virginia.
The Harrell Formation was first described by Charles Butts in 1918. Hasson and Dennison (1978) state "The Harrell Shale consists of very dark gray, thinly laminated, platy- to sheety-weathering shale underlain in certain areas by the grayish black shale of the Burket Member."
Hasson and Dennison reported the following fossils from several outcrops of the Harrell:
Type locality is at Horrell Station, Blair County, Pennsylvania (40°27′N 78°17′W / 40.450°N 78.283°W).
Relative age dating places the Harrell in the late Devonian.
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