Petrochemistry and Depositional Environment of Permian Coals of Basundhara Block, Ib-Valley Coalfied, Orissa,India

Abstract

This paper deals with the characteristics of coal formation. A large number of pillar coal samples from Basundhara
block were collected and subjected to detailed petrograplhic and geochemical studies. The results show that the Basundhara
block (Rampur seam) coals are rich in inerinite group macerals. The rank of Basundhara block coals as per ASTM system and according to the mean of random vitrinite reflectance has been found to range between sub-bituminous '`A' and high volatile bituminous 'B', The proximate analysis exhibit that coals belong to semi-coking to weakly coking range. The ultimate composition shows hydrogen ranges between 4.87 and 6.20%, carbon from 78.7 to 86.3% and oxygen between 7.26 and 13,78% The nitrogen ranges from 0.71 to 0.76% and sulplur is between 0.53 and 0.96%. The  quantitative study of macerals, microlithotypes and mineral matter indicate that these coals originated from the plant communities of highly fluctuating oxic and anoxic moorto oxic (dry) moor with sudden high flooding conditions. Low value of Tissue Preservation Index (TPI) and high value of Gelification Index (GI) indicate peat formation in dry
condition.