Publications

Pertamina EP is operating a small block in Offshore North Sumatera Basin where a couple of the fields are producing gas and condensate from the Belumai Carbonate. However, the wells production is depleting and several delineation wells are unable to find additional reserves, it is important to find a new play within the block. Few discoveries in the Middle Baong Sand (MBS) reservoir suggested a promising stratigraphic play to be explored, but it requires more detailed characterization of the reservoir extent. The Malacca strait-sourced MBS consists of several deposited sand packages during a mega sequence. The term MBS might represent a deltaic environment from a transgressive system tract of some marine shore bar or a basin floor fan. Each system has a distinct character (thickness, net to gross ratio, distribution) that must be evaluated before proposing an exploration well. The depositional environment and reservoir distribution are interpreted and modeled using regional 2D seismic and high-quality 3D seismic. Paleo-bathymetric interpretation from well samples shows a good correlation with the palinspastic reconstruction. The result shows that the Pertamia EP working area is located in the shore bar depositional environment. Seismic attributes are used to delineate reservoir distribution within the working block and well logs are used to constrain prospective sand bodies and water zones identification. Furthermore, source rock maturation and migration path and hydrocarbon occurrence from the discovery wells have been evaluated for hydrocarbon prospecting and risking. This study suggests a promising lead for hydrocarbon exploration in the study area and opens up a new opportunity for an underexplored play.