Publications

The South Sumatra Basin is part of a back arc basin located on the southwest edge of the Sunda Shelf. This basin represents the largest oil-producing basin in Indonesia. Petroleum system in South Sumatera Basin showed that Air Benakat Formation is good reservoir, and most explorationists concern and continue to search for oil and gas reserve in this formation. The Air Benakat Formation are volcanoclastics occurrence have complexity of the reservoir compartment due to inconsistent log reading. Based on our research, we have the best method to correlate in the volcanoclastics sediment of Air Benakat Formation. This research aims to reveal the high resolution sequence stratigraphy of the “volcanoclastics” sediment of Air Benakat Formation. The analysis includes conventional core, biostratigraphic, petrography, formation micro-imager (FMI) logs, optimalizing e-logs evaluation of resistivity, density (RHOB) and neutron (NPHI) analyses since the gamma-ray log showed the inconsistency features and brought into misleading interpretation in “volcanoclastics” sediment of Air Benakat Formation. The result shows ten facies were identified in the study area, including reappearance of four typical facies in coarse grained braid delta environment and six typical facies in tidal-wave dominated delta to barrier bar environment. There are overall nine sequences were identified, one of the sequence boundary which is named as Sequence-5 is determined as regional sequence boundary. The coarse grained braid delta facies composed of braid delta plain, braid delta front and braid prodelta. Most of the coarse grained braid delta facies contain of tuffaceous pebble to conglomeratic sandstone, shale and tuff as products of volcanic active stage. The tidal-wave to barrier bar facies consist of tidal channel, tidal bar, sand flat, mixed flat, mud flat and barrier bar facies. The tidal-wave to barrier bar facies composed of sandstone and shale that deposited during non volcanic active stage. It is concluded, the lithofacies product during non volcanic active stage in the study area have better quality reservoir than volcanic active stage.