Publications

Bone Basin is located between Southeast arm and South arm Sulawesi, precisely on Bone Bay. Bone basin formed through Paleogene to Neogene as a result of extensional force in Miocene. This basin tends to accumulate sedimentary deposits that partake a petroleum system potential near the area of Bone Bay. Proven petroleum plays are shown by oil and gas discoveries in several locations nearby Bone Basin (eg: East Sengkang Basin). However, the understanding of the petroleum system in Bone Basin, especially about the organic geochemistry of active source rock, is still poorly understood. New insight into Bone Basin is based on surface geochemical exploration that came up with 80 core samples using piston core. Geochemical analysis was conducted in 80 surface piston core samples extracted analyzed based on the premise of light hydrocarbons containing migrated thermogenic gas from the reservoir can be detected in near-surface sediments. Some analysis including Total Scanning Fluorescence (TSF), Unresolved Complex Mixture (UCM), and Thermogenic/Diagenetic n-Alkane Ratio were used as indicators to qualify the presence of migrated hydrocarbons. From the extract indicators and interstitial gas indicators, 12 cores are qualified as containing migrated liquid petroleum and migrated thermogenic gas. Afterward, normal alkanes and isoprenoid acyclic from GC analysis were examined to identify the biomarker parameters that useful for the depositional environment, maturity, lithology, and oxicity interpretation. According to the value ratio of Pr/Ph, Ph/n-C17 also Pr/n-C18, most of the samples have intermediate ratio value which suggests that it is derived from lacustrine shale source rocks that were deposited under oxic condition. Furthermore, according to the OEP value, it is determined that the source rock was partly matured and early mature/immature. The result of this study opens up a new understanding of the active source rock in Bone Basin and have broad implication for the future exploration strategy.