The strata of the Tygart Valley in Taylor and Barbour Counties, West Virginia consists of Pennsylvanian age sedimentary strata of the Monongahela Group, the Conemaugh Group, and the Allegheny Formation. The gently dipping layered strata consists of shale, sandstone, claystone, fireclay, and coal seams. At present, economic sedimentary deposits are limited to coal.
The Monongahela Group includes the Sewickley, Redstone, and Pittsburgh coal seams. The Pittsburgh seam has been heavily surface-mined and deep-mined at higher elevations in the Tygart region.
The Conemaugh group coal seams include the Elk Lick, Harlem, Bakerstown and Brush Creek coal seams. These seams are generally thin and discontinuous on the Leer South property. No known mining has taken place in the Conemaugh group coal seams in the Leer South mine area.
The Allegheny Formation includes the Upper and Lower Freeport coal seams, Johnstown Limestone, Upper and Lower Kittanning coal seams, the Clarion and Brookville coal seams. The Upper Kittanning, Lower Kittanning and Clarion seams have been deep mined in the Leer South area. All other coal seams of the Allegheny Formation in the area occur in limited areal extent and are of insufficient thickness for mining. The Upper Kittanning coal seam has had limited mining in the area, often hampered by soft floor strata and high sulfur content.
Leer South is currently mining the Lower Kittanning seam.
Lower Kittann ........