Study Of Maturation Trend And Utilization Characteristics Of The Oligocene Coals In Makum Coalfield, North Eastern India


Ranjan Kumar Sarmah


The Makum Coalfield is located in the Tinsukia district of Assam, India. The coal measure sequence of Barail Group(Oligocene) contains the thick, workable coal seams and the present study is based on field and petro-chemical data of coals.Maturity of sediments shows a vertical increasing trend with depth indicating the role of burial tectonism and dynamic folding. Time temperature index values for the coal basin are strongly indicative of oil generation and occurrence of oil with API gravity less than 400. The study indicates that the coals have attained high volatile Bituminous C to A stage. The Makum coals are classified mostly as per-vitrinous coals and only a few as meta-vitrinous coal types. Seyler's classification places the coals of the study area in per-hydrous type but the younger seams show sub-hydrous character.. Correlation between volatile matter and H/C ratio does not show any distinct trend from younger to older coal seams; however, high volatile matter content in the coal seams is evident. Evaluation of coal quality and utilization of the coals have been attempted.