Indiana Paper Coal: Composition and Deposition

Abstract

ABSTRACT The term previously applied to a coal in the U.S.S.R., describes a coal found in Parke County, Indiana. In contrast to the Russian coal, which consists of cuticles of arborescent lycopods, the cuticles of the Indiana paper coal resemble Sphenopteris bradfordii Arnold, the foliage of a seed fern. Exinite (cuticles and spore exines) constitutes 23.5 percent of the coal seam where it is unweathered. The papery texture occurs only where weathering has removed the vitrinite and has left a mat of resistant cuticles. Spore analyses indicate that the seam is one of the upper Pottsville coals. Many sporangia from the paper coal are composed of small, round non-sutured spores and an outside layer of spores resembling Torispora Balme. Cutinization suggests that these plants could store water. Fresh water periodically feeding into a saline swamp could have been adequate to sustain these xerophytic plants. Trace element analyses substantiate the belief that water conditions were predominantly marine. Cutinite isolated from the coal has a calorific value of 16,700 B.T.U. per lb and a volatile matter content of 85 percent on a dry, ash-free basis. Because cutinite has such a high volatile matter content similar cuticular coals possibly can be utilized most efficiently as hydrocarbon sources.