Abstract

The subject of detection of abnormally high pressured zones from seismic has received a great deal of attention in exploration and production geophysics because of increasing activities in frontier areas or offshore and a need to lower cost without compromising safety and environment, and managing risk and uncertainty associated with very expensive drilling. An estimation of pore pressure can be obtained from seismic velocity as well as from well logs. Using interval velocity volume to estimate pre drill pore-pressure, but the seismic velocities need to be derived using methods having sufficient resolution for well planning purpose. Velocity field obtained using a conventional method based on the Dix equation. Parameters in the velocity- OBGNCT-to- pore-pressure transform are estimated using seismic interval velocity and pressure data from nearby calibrated wells. The uncertainty in the pore pressure prediction is analyzed by examining the spread in the predicted pore pressure obtained using parameter combinations which sample the region of parameter space consistent with the available well data. Whenever we go for a virgin area, seismic would be more reliable since it is spatially well sampled and we can reached up to the bottom of the seismic volume. On the other hand pore pressure prediction from well logs is accurate at a particular point only, but they are spatially limited. It has also depth limitation. By bringing the two together secrets hiding in subsurface data can be revealed.