Publications

The hydrocarbon occurrences within the Northeast Java Basin (NEJB) indicate that the area is primarily oil-prone. The Miocene Kujung Limestone holds most of the hydrocarbon resources and appears to be overexplored, but the Paleogene interval remains underexplored in this region. The current study will look solely at the sub-basin containing undrilled Paleogene carbonate. The G&G evaluation uses the KKPJM dataset and the technique is based on a play-based exploration workflow, from basin to play focus, followed by lead and prospect identification. The identified source rocks were sequence A, sequence B, sequence C, and sequence D. Most of hydrocarbon generation is believed to be coming from sequences A and B. Most of the first traps of Paleogene carbonate play suggest that the trap is placed near to the charge access. The Paleogene carbonate build-up seismic character forms mounded structure with onlap features, located in the Ngimbang Low. These build-ups can be mapped in the Pagerungan sub-basin area. Based on the subsurface data, the Paleogene carbonate can be divided into reefal in the lower part and carbonate debris in the upper part of the sequence; the porosity average of Oligocene carbonate is about 15%. H-1 well ecountered Ngimbang Eocene carbonate, reported to have good porosity and excellent permeability with strong indication of the karstification. The carbonate reservoir is dominated by muddy limestone, with strong indication of reworked carbonate materials existance. The Paleogene carbonate play likely extends further east northeast with potential presence of many untested closures. Exploration opportunities of Paleogene carbonate in the Ngimbang Low, North Madura, and Pagerungan sub-basins remain very promising with a lot of potential drillable buildups are identified.