Abstract
Asri Basin is known for its large oil production in the western part of Indonesia, with reserves approximately 1.2 billion barrels and cumulative production has reached more than 500 million barrels oil (Yumansa, 2013). By knowing this fact, it is essential to analyze the maturity of source rock which produced the hydrocarbon. Our intention in this research is to give information about the potential of Asri Basin’s source rock according to kerogen type obtained from our analysis using regional stratigraphy and geochemical log data. Asri Basin is a Paleogene half-graben which curved toward the southwest, and confine the major fault in the east. It is located about 150 km to the southeast offshore of Sumatra Island. Based on regional stratigraphy, lacustrine shale in Banuwati Formation conformable with terrestrial – lacustrine sediments in Talang Akar Formation which both of them have a potency being a source rock. Geochemistry data shows the kerogen type 1. Lacustrine sediment has rich organic content that suitable to produce good oil. Yumansa (2013) stated that Eocene Banuwati lacustrine shale is the only active source rock which is known to produce hydrocarbons in Asri Basin. The present of oil window is estimated to be at 11,500 feet below sea level. Through this research can be define the potential source rock in Asri Basin.