ABSTRACT

Proximate analyses and petrographic measurements were made on fourteen lignite outcrops from Lower Eocene Wilcox Group sediments in Choctaw and Winston counties in central Mississippi. The lignite exposures appear to be irregular in shape, limited in areal extent, and variable in seam thickness. Locations of lignite deposits appear to be related to ancient fluvial systems, and the shapes and areal extent of the lignite deposits appear to have been determined by the configuration of the ancient basins in which the coal-forming vegetal matter accumulated.

Twelve of the lignite seams showed a negative correlation between ash content and seam thickness. Most of the lignite seams investigated petrographically show a dominance of humodetrinite, indicating that the lignites were formed from herbaceous, cellulose-rich/lignin-poor marsh plants. Several well preserved tree trunks obtained from two lignite seams have been identified as being taxodiaceous and dicotyledonous which indicates a fresh water marsh/swamp environment associated with the lignite deposits.