Abstract: In order to study the propagating rules of pure compress wave and pure shear wave of the hybrid elastic wave field more accurately, the general method is achieved by the operator separation to construct equivalent first-order hyperbolic type elastic wave equation to achieve the elastic wave field separation numerical modeling, which increases not only the computed memory and computed time, but also the computing complexity. In order to solve the above problems, the paper puts forward a quick elastic wave field separation numerical modeling scheme base on staggered-grid and second-order elastic wave equation, according to which the pure compress wave (divergence field) and pure shear wave (curl field) are calculated with layered model and a complex model with solid-fluid. The numerical result shows that this method can correctly separate pure compress wave and pure shear wave from hybrid wave field with high precision and high efficiency, and the paper also indicates the method's inapplicability of the wave on the surface of solid-fluid and so on.

Key words: high-order staggered-grid, wave field separation, elastic wave equation, divergence and curl, VSP