Integrated Fault and Top Seals Study in South Sumatra Wrench Basin

The overprinting of pre-Tertiary structures and Paleogene rifting has created a series of half-graben with NE-SW and N-S trends in South Sumatra Basin. Plio-Pleistocene wrench tectonic then uplifted the basin and creating traps as well as promoting hydrocarbon migration (and leakage) through faults and weakness point of capillary seal. Despite the proven hydrocarbon fetching area and migration focal point, trapping mechanism in Rimau Block still becomes a challenging factor. This paper is aimed to evaluate the main factors that controlling trap and seal quality, which consist of: (1) Structural evolution, (2) Capillary entry pressure, and (3) Caprock/seal facies. Kinematic restoration was applied to reconstruct basement movement in the rift stage as well as inversion characteristic responsible for Plio-Pleistocene petroleum entrapment. Moreover, careful evaluation about the connection between seal depositional setting and MICP measurement was made in order to understand the involvement of fault and lateral stratigraphic seal on petroleum seal capacity. The identification and application of the seal integrated study is expected to minimize risk and improving volumetric calculation criteria for future exploration and development projects.