Method and system for pre-drill pore pressure prediction

In general, the invention relates to a method for pore pressure prediction. The method includes obtaining a compressional wave (P-wave) velocity and a shear wave (S-wave) velocity for a pre-drill location, calculating an effective stress at the pre-drilling location using a stress-velocity relationship equation, the compressional wave (P-wave) velocity and the shear wave (S-wave) velocity, obtaining a total stress at the pre-drill location, calculating a predicted pore pressure, at the pre-drill location, using the effective stress, the total stress and a stress-pressure relationship equation, and adjusting a drilling operation associated with the pre-drill location, based on the predicted pore pressure.