Dual Elastic Wave Wavefield Separating Simulation Method and Related Theory Derivation

We present an equivalent dual elastic wave separation equation, which simulates particle-velocity, pressure, divergence and curl fields in pure P- and S- modes. The method is used in full elastic wave numerical simulations. We give complete derivations of explicit high-order staggered-grid finite difference discrete equations, together with stability condition, dispersion relation and perfectly matched layer (PML) absorbing boundary condition. Theoretical analysis and numerical simulations show that pare P-waves and S-waves in final numerical results are completely separated in the method. Effect of absorbing boundary is perfect. Storage and computing time requirements are greatly reduced compared with previous works.