Simulating propagation of decoupled elastic waves using low-rank approximate mixed-domain integral operators for anisotropic media

conclusions

We have proposed a recursive integral method to simultaneously extrapolate and decompose the elastic wavefields on the base of second-order displacement equation for heterogeneous anisotropic media. The computational efficiency is guaranteed by merging the operations of time extrapolation and vector decomposition into a unified Fourier integral framework and speeding up the solutions using the low-rank approximation. The use of the $k$ -space adjustment permits larger time-steps without reducing accuracy or introducing instability in the low-rank pseudo-spectral scheme. The synthetic example shows that our method could produce dispersion-free decoupled and total elastic wavefields efficiently. We expect that the proposed approaches to extrapolate the decoupled elastic waves have great potential for applications such as elastic RTM and FWI of multicomponent seismic data acquired on land and at the ocean bottom. The focus for future work will be on the staggered-grid pseudo-spectral solution of the displacement-stress or velocity-stress equation for anisotropic media with strong heterogeneity and lower order of symmetry.

Simulating propagation of decoupled elastic waves using low-rank approximate mixed-domain integral operators for anisotropic media