Paleogeography of a Middle Pennsylvanian coal seam in the eastern Kentucky coal field

The middle Pennsylvanian Upper Elkhorn No.3 coal bed of the Breathitt Formation represents a swamp facies of a fluvial/deltaic complex eroded from the Appalachian hinterland. Geologic conditions during the peat formation and burial stages of the coal were determined by correlating measured sections, using maps of the thickness, number of partings, roof lithologies, and sulfur- ash-, and Btu-content of the Upper Elkhorn No. 3 coal. A paleogeographic reconstruction of the peat stage shows areas of marine-influence, in addition to well-protected and poorly-protected swamps. The peat swamp which deposited the coal developed on a very broad coastal plain consisting of deltaic-type sediments with increasing terrestrial conditions to the east and increasing marine conditions to the west. Prograding fluvial systems buried peat initially deposited in brackish to marine environments of the flood-basin. Pre-mining basin analysis leads to more effective exploration and exploitation, in particular coal quality (including sulfur and ash content), mineability, roof lithology and locations of channels can be predicted before mining.