The South Sumatra Basin is one of mature basins in Indonesia. Bordered by exposures of crystalline basement and pre-Tertiary metasediments in the Tigapuluh Mountains to the North, Bukit Barisan to the South, Bangka to the East, and Lampung High to the Southwest. The Baturaja Formation is one of the sweet reservoirs that has composition of limestone, dolomite, claystone, and shale from Lower Miocene period, located above the Talang Akar Formation. The basinal facies, the deepest and thickest, is characterized by low-energy, clay-rich carbonates, with a mix of grain and mud support. Granular fabric composed of faunal debris, silt, and fine-grained detrital material, primarily glauconite and terrigenous quartz and fauna dominated by planktonic and benthonic foraminifera, as well as fragmented pelecypods and echinoderms while porosity is intergranular and relatively low. The basinal facies gradually changes into the stable shelf facies and, in some areas, into the reef facies as it moves up-dip.

In 2022, PHE Jambi Merang explored the Southern area of the Jambi Merang Block with the primary target being Baturaja Formation. Seeing in the evaluation of 3D Seismic 2012 with PSTM and PSDM enhancement, the build-up of the carbonate structure is clear and gentle from the perspectives of seismic stratigraphy, seismic analysis, and geological concepts. This is evidenced by the drilling results, with discovery up to 13 MMCFD of gas and associated condensate above 200 BCPD. Post-drill evaluation showed that the “SS” structure is still good and feasible to develop. Proving up that the exploration target with the existing play in the South Sumatra Basin is still promising at present and into the future.

Keywords: South Sumatera Basin, Baturaja Formation, Seismic Stratigrap