A simple method for resolving large converted-wave (P-SV) statics

The processing of converted-wave (P-SV) seismic data requires certain special considerations, such as commonconversion-point (CCP) binning techniques (Tessmer and Behle, 1988) and a modified normal moveout formula (Slotboom, 1990), that makes it different for processing conventional P-P data. However, from the processor's perspective, the most problematic step is often the determination of residual S-wave statics, which are commonly two to ten times greater than the P-wave statics for the same location (Tatham and McCormack, 1991). Conventional residualstatics algorithms often produce numerous cycle skips when attempting to resolve very large statics. Unlike P-waves, the velocity of S-waves is virtually unaffected by near-surface fluctuations in the water table (Figure 1). Hence, the P-wave and S-wave static solutions are largely unrelated to each other, so it is generally not feasible to approximate the S-wave statics by simply scaling the known P-wave static values (Anno, 1986).