Haripur Oilfield

Haripur Oilfield The only oilfield so far discovered in Bangladesh. Commercial accumulation of oil was discovered in Haripur, Sylhet, in December 1986 while drilling appraisal cum production well Sylhet-7 in Sylhet gas field. Haripur oilfield is located in Sylhet district about 20 km northeast of Sylhet town and beside the Sylhet Jaintia road. It is a small oilfield, which produced only for about seven years before production was suspended. The oilfield is located in the Sylhet anticline, a northeast southwest trending fold structure with a length of 13 km and a width of 3 km. The stratigraphic units encountered in the oilfield are, from bottom upward, Boka Bil Formation, Tipam Formation, Girujan Clay Formation and Dupitila Formation. The lowest unit, the Boka Bil Formation, consists of alternating sand and shale beds. The sandstone beds of the Boka Bil unit are designated from top downward as 'A' sand, 'B' sand, 'C' sand, 'D' sand and 'E' sand. In the Haripur-1 well only the 'E' sand is oil bearing while the other Boka Bil sands above are gas bearing. The oil bearing sand is about 13 meter thick and occurs at depths between 2020-2033 meters below the surface. The Haripur oil is dark brown, waxy and paraffinic type. It is medium density oil with an API gravity of 29o. The oil contains insignificant sulfur (0.3%). Chemical analysis revealed the presence of abundant bicadinanes, a biomarker that indicate land plant origin of the oil. On refining the Haripur oil produced 18% petrol, 17% kerosene, 35% gas oil and 30% lubricant plus residue. Haripur oilfield is a small size field by international standard. Petrobangla had determined the oil reserve by volumetric method and estimated the stock tank oil originally in place (STOOIP) to be about 10 million barrels. Oil and Mining Services, consultants to Petrobangla had carried out estimation of oil reserve by material balance method using pressure and production data till1987 and showed the STOOIP to be 8 million barrel. Oil productions from Haripur oilfield started in January 1987. The well ceased to produce oil since July 1994. Production was suspended because of decline of oil flow and excessive watert output. Until the suspension of operation in 1994 the cumulative production of oil from the Haripur oilfield was about 0.56 million barrel. During the time Haripur oilfield was in production, the average demand of oil in Bangladesh was about 37,000 barrel a day. It thus appears that Haripur field could not supply any significant share of the national oil need. [Sanzida Murshed] [Murshed, Sanzida Lecturer in Geology, Dhaka University]