Seismology and Seismo-Acoustics

This chapter covers parabolic equation techniques for elastic waves, which include compressional, shear, boundary, and interface waves in solid materials. Compressional waves correspond to longitudinal motion (parallel to the direction of propagation) and perturbations in volume. Shear waves correspond to transverse motion (orthogonal to the direction of propagation) and perturbations in shape. Boundary and interface waves propagate along boundaries and interfaces and decay exponentially in the transverse direction. Applications of the elastic parabolic equation include seismology and ocean acoustics problems in which the ocean bottom or ice cover supports shear waves.