A High Order Finite Difference Method for the Elastic Wave Equation in Bounded Domains with Nonconforming Interfaces

We develop a stable finite difference method for the elastic wave equation in bounded media, where material properties can be discontinuous at curved interfaces. The governing is discretized second order form by fourth or sixth accurate summation-by-parts operator. mesh size determined velocity structure of material, resulting nonconforming grid interfaces with hanging nodes. use order-preserving interpolation and ghost point technique to couple adjacent blocks an energy-conserving manner, which supported fully discrete stability analysis. In our previous work equation, two pairs operators were needed when imposing interface conditions weakly penalty technique. Here, we only one pair method. numerical experiments, demonstrate that convergence rate optimal same as globally uniform used single domain. addition, predictor-corrector time integration method, obtain stepping stepsize almost given usual Courant--Friedrichs--Lewy condition.