Petrology of the Pittsburgh coalbed (Gzhelian (Stephanian C), Monongahela Group/Formation) in Pennsylvania, West Virginia, and Ohio

The Gzhelian (Stephanian C)-age Pittsburgh coal in southwestern Pennsylvania, eastern Ohio, northern West Virginia, and western Maryland has been mined since the 1700's. The coal contributed up to 80% of the US coking coal in the 1880's and continued to be an important source of coking coal through the 20th century. This high-vitrinite coal decreases in rank from medium and low volatile bituminous in Somerset County, Pennsylvania, and in adjacent parts of Maryland to high volatile C bituminous in Ohio, a distance of about 170 km. Detailed studies of the petrology and coking characteristics of the coal were conducted by Thiessen, Strunk, and others at the U.S. Bureau of Mines in the 1930's, and Aureal Cross conducted detailed petrographic and paleobotanical investigation in the 1950's. Later studies have examined the petrology and palynology of the coal in northern West Virginia. In this investigation, the coals collected by the Penn State Coal Research Section are re-examined in the light of modern coal petrographic nomenclature. Telovitrinite macerals generally dominate the vitrinite group and fusinite and semifusinite, along with minor macrinite, micrinite, and secretinite, comprise the inertinite group.