Raniganj Coalfield records mining since eighteenth century. Still, the geology of the south-eastern part of the coalfield, developed in the Trans-Damodar Sector was not adequately known owing to very poor outcrop of rocks being almost entirely covered with lateritic or alluvial soil. However, later subsurface study was done, and established occurrence of coal bearing rocks, particularly of Raniganj and Barakar Formation at relatively shallow depth. The outcome of the exploration has proved that the central part of the area is more promising as compared to the northern and southern parts. In the present work, the coal seams developed in the Borjora coal field area in the Trans-Damodar sector have been examined through two studies, namely variation in thickness and variation in ash content which in turn is very important to determine the ultimate usability of coal. The book will also give the preliminary idea for interpreting the basin morphology as well as in establishing the nature of environment of deposition.