Velocity Based Pore Pressure Prediction - A Case Study at One of the Iranian South West Oil Fields

摘要

Porepressure is one of the important concepts in hydrocarbon exploration and drilling.Abnormal pore pressures are encountered worldwide, often resulting in drilling problems such as kicks, blowouts, borehole instability, stuck pipe, and lost circulation. Thus quantitative predrill prediction of pore pressure is required for the safe and economic drilling of wells in overpressured formations. In addition, porepressure maps can be used to study hydrocarbon migration paths and cap rock quality. In this paper we tried to generate a reliable velocity model by combining stacking velocities, acoustic impedances from seismic inversion and available sonic well logs using geostatistical techniques. We used Bower’s velocity to pressure transformation that calibrated with offset wells. finally all the results checked and controlled. The quality control step reveals that despite of geological complexity we faced in this field, our final results are satisfactory and the method we used has been appropriate.