THE CHARACTERIZATION OF MACERAL COMPOSITION IN THE LEATHERWOOD COAL BED IN EASTERN KENTUCKY

The Eastern Kentucky Coal Field is located in the central portion of the Appalachian Basin, extending from the Appalachian Mountains westward across the Cumberland Plateau. The Pennsylvanian Breathitt formation in this region is characterized by numerous sequences of bituminous coal-bearing sedimentary rocks. Many of these coals have distinct maceral compositions due to variations in depositional environments. Because Kentucky contains coal of differing maceral assemblages, coal characterization is an important method for determining conditions that influenced peat accumulation and overall depositional settings.

This study focuses on the characterization of the maceral composition of the Middle Pennsylvanian-age Leatherwood coal bed through palynological, petrographical, and geochemical analyses in order to better understand specific depositional environments and associated peat accumulation conditions.

The high volatile A bituminous Leatherwood coal consists predominately of alternating clarain and vitrain lithotypes. Petrographic analyses indicate that these coals are dominated by vitrinite, primarily collotelinite. These coals have relatively high liptinite and low inertinite content, along with trace amounts of mineral matter. Geochemical data reveal low sulfur and ash content. Ancillary palynological data shows that the palynomorph assemblage is dominated by tree fern spores, with limited amounts of small and large lycopsid tree, small fern, and Coradites sp. spores. The maceral composition and corresponding palynological data indicate that the depositional environment was most likely a ponded-water mire community, characterized by relatively consistent water depth, anaerobic conditions, and limited local detrital influx.