Bangladesh – Oil & Gas 2021

Natural gas, played vital role as main energy source to the rapid development of Bangladesh, production and consumption has been increased drastically during last decades. Geological and geophysical explorations have identified significant quantities of natural gas reserves in Bangladesh. Proper reservoir characterization is very important in estimating the actual amount of gas reserve. Fortunately, there are 27 gas fields in Bangladesh till now. In 1993, the initial estimated recoverable gas reserve was around 12.43 TCF. The amount became around 26.84 TCF by 2011 and finally grew to 27.12 TCF at the end of 2017. From this amount, around 15.22 TCF gas has already been produced. So, the remaining 12 TCF gas can be used for future use. Moreover, it is projected that the country would be able to fulfill the growing demand of natural gas for the next 10–12 years with the remaining gas reserve. It is therefore an urgent need to increase the amount of gas reserve. To discover a new gas field would contribute significantly to the total gas reserve but it is time taking and cumbersome. An alternative and effective way is to the development of existing gas fields to increase the gas reserve termed as “reserve growth”. It is evident that reassessment of reservoir properties with latest techniques would increase the amount of gas reserve significantly. This study thus finds that reassessment of reservoirs characteristics in Bangladesh gas fields can be done using new techniques such as detailed digital reservoir characterization technique which might increase the total gas reserve.

Bangladesh is a land of geo-resources with covering an area of 147,610 square kilometers extending from 820 km north to south and 600 km east to west. Geographically, Bengal Basin is located in a region with very high tectonic activities. Many active tectonic elements are present in and around the Bengal Basin. Such as the on-going Indian and Eurasian plates collision mountain range in the north, the Shillong plateau in the northeast, the folded mountain belt between the obliquely subducting Indian plate and overriding Burma plate in the east. The uplifting of Himalayan orogeny in north of Bengal Basin results building up of a large landmass, formation of mega delta by the major river system (Ganges-Brahmaputra-Meghna) originated from the uplifted Himalayan mountain belt. The on-going collision between the Indian and Burma plates in the east of Bengal Basin forms series of structural elements favorable for the formation and accumulation of hydrocarbon. Such as the Morichakandi structure is situated in the western most part of the Chittagong-Tripura folded belt and is a symmetrical anticline with SE-NNE. As the mega delta moves southwards accompanied by rapid subsidence of the basin, a huge thickness of deltaic to fluvio-deltaic sediment was deposited and the eastern part has been uplifted into hilly landform incorporating itself into the frontal belt of the Indoburman Range. The deposition of huge deltaic sediment, erosion and folding due to thrusting eventually leads different compaction trend and affects the reservoir storage capacity of reservoir rock as well as the sealing capacity of the cap rocks. As a result, Bengal Basin is one of the most gas-bearing and productive basins in Southeast Asia.