Using refracted shear waves for velocity estimation

The most difficult parr of multicomponent processing is the estimation of t he shear-wave velocity map for migration. We used refracted shear waves and a simple iterative method called wavefield continuation (WFC) to evaluate the shallow shear-wave velocity profile on a real data example. The WFC was developed in 1981 by Clayton and McMechan to determine compressional-wave velocity profiles from refracted compressional waves. The application to re fracted shear waves is straightforward. The real data example shows that sh ear structure can be easily determined independently of the compressional s tructure.