Abstract

All the gas fields are located in and near the frontal fold belt of the Indoburman Ranges in the eastern part of Bangladesh. The gas is confined in the crests of the anticlines and the sand reservoirs are mainly of Miocene age. The traditional method of correlation on the basis of lithological criteria alone of the Neogene deltaic foredeep sequences of the Bengal Basin from Assam to southern Chittagong Hill Tracts is untenable and this long standing problem can be resolved with the help of palynology.

Results of isotope analyses of gases of Bangladesh gas fields indicate that the natural gas is derived from marine source rocks and was generated well within the “oil window” of maturation. Geochemical data known so far suggest that the marine source rocks of the present natural gas are of Paleogene or even older age.

The total recoverable reserve of natural gas is estimated to be 10.0 trillion cubic feet. Since the gas fields are not adequately explored, the true extent of the reservoirs is not precisely known. The gas is essentially methane, practically sulphur free, and has a high calorific value. It is used in fertilizer and power plants as well as in industrial, commercial and domestic sectors.