Publications

The Neogene (23 – 2.6 Ma, including Miocene and Pliocene epochs) is a very important period for Indonesian geology. In this period Indonesia got its present configuration and became the main time controlling the geological setting for the occurrences of energy and mineral resources, as well as geologic disasters. There are important differences in the geological evolution of the Neogene between the western and eastern parts of Indonesia. In Western Indonesia, the outline of the evolution is that transgression occurred in all basins with maximum transgression occurred by the end of early Miocene. Then followed by compression and inversion tectonic events as well as regressive sedimentation from the mid-Miocene to the Pliocene in Sumatra, Natuna, Java basins; while deltaic sedimentation characterized the period in eastern Borneo basins. Volcanism became an important element in the Neogene for Sumatra, Java, Lesser Sunda. In Eastern Indonesia, during the Miocene there was drifting of terranes and their syn-drifting sedimentation, then the terranes collided and were fragmented in the Miocene-Pliocene followed by the formation of regional strike-slip faults, subduction rollback, and the opening of the Banda Sea. The period was also characterized by post-collision molassic sedimentation into the foreland basins. These geological events strongly controlled the petroleum system in every basin in Western and Eastern Indonesia. Although some elements of the petroleum system are Paleogene or Pre-Cenozoic in ages, most of the petroleum system processes associated with final trap formation, petroleum generation, migration, accumulation, and preservation of accumulation occurred in the Neogene. The deltaic basins of Kutai and Tarakan in Western Indonesia and the carbonate basins in Eastern Indonesia (Salawati and Banggai) have their proven petroleum system elements and processes within the Neogene period. Thus, studying the geological evolution and its implications for the petroleum system in the Neogene is very important. The knowledge of this can be applied particularly to less explored basins in Indonesia which are geologically analogue to the productive basins.