An optimized variable-grid finite-difference method for seismic forward modeling
نویسندگان
چکیده
An optimized fourth-order staggered-grid finitedifference (FD) operator is derived on a mesh with variable grid spacing and implemented to solve 2-D velocity-stress elastic wave equations. The idea in optimized schemes is to minimize the difference between the effective wave number and the actual wave number. As expected, this optimized variable-grid FD scheme has less dispersion errors than the variable-grid FD scheme based on Taylor series expansion with the same stencil. The accuracy of the proposed technique has been tested through the comparison with the analytical solutions and the regular-grid FD method based on Taylor series expansion. The effectiveness of the method is verified by its application for a thin-layer model.
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