2D FREQUENCY-DOMAIN FINITE-DIFFERENCE ACOUSTIC WAVE MODELING USING OPTIMIZED PERFECTLY MATCHED LAYERS

Seismic forward modeling is fundamental in sensitivity analysis and full waveform inversions. In finite-difference acoustic wavefield simulation, the absorption boundary, especially the perfectly matched layer (PML), is widely used, but the setting of PML parameters is empirical. This paper proposes an optimized complex-frequency-shift PML (CFS-PML) for modeling of acoustic fields. It refines the selection of parameters for improving the artificial attenuation. The improved CFS-PML boundary condition is applied to a 2D frequency-domain acoustic wave simulation using an optimal 17-point finite difference scheme. Numerical results are compared with a conventional 9-point scheme in terms of computational time and physical memory consumption. These tests indicate that the proposed CFS-PML absorption boundary can effectively improve numerical accuracy without increasing the computational burden remarkably.