A New Discovery in The Limau Graben Trend: Air Benakat Formation Shallow Gas

Abstract

Many hydrocarbon fields in the Limau Graben trend were produced in the 1950s. That fields are mostly produced in the Talangakar Formation and Baturaja Formation. To maintain the continuity of production, the discovery of new reservoirs is a target that must be carried out in the subsurface analysis. Air Benakat Formation becomes a discovery that shows good results. Air Benakat Sand is characterized by thin sand 2 – 5 meters funnel log pattern, silt to very fine sand grain deposited in the shallow marine based on core analysis. The resistivity is 1.5 – 4 ohms, showing a low resistivity reservoir caused by high laminated clay content and conductive minerals. In order to understand the distribution of Air Benakat Sand, RMS amplitude was extracted from seismic data, and combined with the fault interpretation. Fault bounded area with high RMS amplitude (up to 6), and resistivity of 1 – 4 ohms were selected for the candidates of new well perforation and step out. The result of the well testing in the selected well reveals a gas flow rate of 1.2 – 2.4 MMSCFD and an oil flow rate of 64 – 160 BOPD.