Petrological investigation of Eocene coals, Garo Hills, Meghalaya, India

Abstract

Investigation of coal of Eocene age from the Garo Hills was undertaken to characterize them petrographically and to discuss on their evolution. The quantitative data shows that these coals are vitrinite rich with poor concentration of inertinite and appreciable amount of exinite group of macerals. According to microlithotype analysis, these coals may be characterized as vitrite rich with minor amounts of clarite, vitrinertite and durite. The dominant minerals are clays, siderite and pyrite. Based on the petrological evidences, the evolution of Garo Hills coals has been discussed. The petrographic characters and presence of teleutospore shows that Meghalayan coals are similar to other Tertiary coal deposits of the world. The maceral and microlithotype composition shows that these coals have originated from fluvial and undisturbed peat in the foreland basin under limno-telmatic depositional milieux.