Pore Pressure Prediction is crucial to prepare a safe drilling program especially if there the well will potentially intersect shallow gas zones. It influences casing design, drilling mud weight and mitigation of overpressure as a drilling hazard. In the Bentu Block, Central Sumatra Basin several wells have experienced blow-outs. These blow-outs led us to conduct a pore pressure study ahead of future drilling. The work more emphasize the technique integrated pore pressure prediction (PPP) brings together well, geological, and seismic data.
The study used as input data from drilling data, wireline logs, pressure tests, and 2D Seismic. Nowadays, seismic technology-based geopressure techniques provide an estimation of pore pressure from seismic velocity combine with seismic inversion where disequilibrium compaction is the dominant pore pressure mechanism. The author uses both seismic inversion and velocity analysis result to obtain a high-resolution velocity cube. Afterward, calibrated to pore pressure using well log and drilling data. The Eaton method is an empirical method to estimate pore pressures from sonic, resistivity and density logs which are calibrated to measured pore pressures from RFT and DST. Reliable pore pressure distribution required an empirical relationship between pore pressure and velocity.
Authors : Ronald Siregar, Radig Wisnu Y, Afrizon Setiawan, Hendarman