Publications

A surprising result from South Saubi drilling campaign has changed the geological map of southern part of East Java Basin, and therefore has also changes the exploration perspective. The distribution of Kujung carbonate, Ngimbang Formation and Pre-Ngimbang /Basement now have become questionable in the region. The Southern Basin exploration well drilled with objective to test Kujung carbonate build up (Oligocene-Miocene) as similar play which proven in the western part of East Java Basin. In order to have a geological success, we need the component of petroleum system to work. The South Saubi source rock, reservoir, migration and timing is a proven petroleum system component East Java Basin and it makes this drilling campaign optimistic in the beginning. Total 1,650 MMBO (Pmean) oil was expected. The most recent 3D acquisition data acquired in 2014 along with the nearby exploration wells result which drilled in the last 15 years also supporting this drilling campaign. The Southern Basin Exploration (SBE) well success in founding Kujung top carbonate as the main target reservoir and TD at 14,630 ft MD in volcano-clastic sediment. No hydrocarbon indication found. The well then P/A with status dry hole. Another exploration prospect in Kangean PSC area named West Southern Basin prospect which lies in the western part of South Saubi prospect. Initially the South Saubi prospect and West Southern Basin prospect interpreted to have similar exploration of Kujung carbonate play. But, the negative result of SBE well has left the expected 1,500 MMBO (Pmean) West Southern Basin opportunity became very challenging. Understanding the role of volcanic activity and its distribution become a key for West Southern Basin Prospect petroleum system. The exploration play in southern part of the East Java Basin might be shifting from the Eocene-Pleistocene carbonates play to the volcanic play.