Three-dimensional parallel frequency-domain visco-acoustic wave modelling based on a hybrid direct/iterative solver

摘要: Wepresentaparalleldomaindecompositionmethodbasedonahybriddirect-iterative solver for 3D frequency-domain modelling of visco-acoustic waves. The method is developed as a engine full waveform inversion. Frequency-domain seismic reduces to the solution large and sparse system linear equations, resulting from discretization heterogeneous Helmholtz equation. Our approach high-performance, scalable systems combine direct iterative methods. Such hybrid exploits advantages both component uses small amount memory provides natural way parallelization. part has favourable numerical properties multiple right-hand side modelling. domain decomposition based upon algebraic Schur complement method, which allows reduced system, wavefield at interfaces between subdomains. Once interface unknowns have been computed, interior each subdomain efficiently computed by local substitutions. solved with generalized minimum residual preconditioned an additive Schwarz preconditioner. A used factorize impedance matrices defined on subdomain. Theoretical analysis shows that time complexity same time-domain approaches single frequency Simulations are performed in SEG/EAGE overthrust salt models frequencies up 12.5 Hz. number iterations increases linearly subdomains given computational but elapsed resolution remains almost constant. also frequencies, when grid interval adapted size kept constant over frequency. These results make cost order finite-difference modeling one-frequency Although one tackle larger problems than directsolver approach, further improvements needed mitigate