Publications

Recent interpretation in the Offshore Matindok Block has provided a better understanding about the architecture of the Banggai-Sula foreland basin. The regional map of Miocene platform carbonate clearly defined several prospects on each wedge-top, fore-deep, fore-bulge and back-bulge areas. Based on petroleum system assessments, the source rock and hydrocarbon migration are the highest risk. Pertamina EP have already drilled 2 (two) exploration wells in offshore Matindok, however both were dry wells. Post drill evaluation has shown that there is a synclinal barrier area, known as Tolo Deep, that acts as the boundary of hydrocarbon migration from the proven kitchen area beneath the batui thrust on the western part to the offshore prospects closure on the eastern part. The hydrocarbon generation of Tolo Deep, which is foredeep of the Banggai-Sula foreland basin, has been internally evaluated but the results are still not encouraging. Other prospective kitchen areas are needed to turn the tables. New Interpretation of the 2D PSDM dataset has shown that there is a possibility of a NE-SW trending graben system, as a product of Mesozoic rifting phase, existing beneath the Miocene platform carbonate. Several studies about Mesozoic petroleum systems in this area such as geological field mapping, geochemical analysis and post drill well report evaluation have already started since the 1980’s. The Loku-1 well, located 300 km from the study area on the northern Mangole Island, penetrated Jurassic shale Buya Fm. with TOC 0.3-1.3 %, HI: 43-375 and kerogen type III (gas prone). Biomarker analysis shows positive correlation between condensate samples found in the fracture basement with Jurassic shale Buya Fm. This concludes that Jurassic Shale Buya Fm deposited in Mesozoic graben system has already reached the ideal condition to generated hydrocarbons. We believe the Mesozoic graben system can be a new potential kitchen area in the offshore Matindok block.