Harrell Shale

Harrell Shale Group
Stratigraphic range: Frasnian
TypeGroup
Sub-unitsBurket Shale
UnderliesBrallier Formation, Sonyea Formation, Trimmers Rock Formation
OverliesMahantango Formation, Millboro Shale, and Tully Limestone
Lithology
Primaryshale, sandstone
Location
RegionAppalachian Mountains
CountryUnited States
Type section
Named byCharles Butts, 1918

The Devonian Harrell Formation is a mapped bedrock unit in Pennsylvania, Maryland, West Virginia, and Virginia.