f Refraction correction on a sonic calibration

Anomalous travel times have been observed in the Seismic acquisition in the highly deviated Morsa West-2 well, Congo Basin, offshore Angola. These anomalies have been interpreted as the refraction of the seismic wavefield at the top of the reservoir due to high impedance contrast between the gas cap and formation reservoir. Derivation of real travel time can be computed from geometric corrections between well deviation and the angle of incidence.