A Multigrid-based Iterative Solver for the Frequency-domain Elastic Wave Equation
نویسنده
چکیده
SUMMARY Efficient numerical wave modelling is essential for imaging methods such as reverse-time migration (RTM) and full waveform inversion (FWI). In 2D, frequency-domain modelling with LU factorization as a direct solver can outperform time-domain methods by one order. For 3-D problems, the computational complexity of the LU factorization as well as its memory requirements are a disadvantage and the time domain becomes more attractive. Recently, it has been shown that with compute cores in abundance, a parallel frequency-domain iterative solver can be a competitive alternative to the time-domain approach for 3-D acoustic RTM. The solver relies on a preconditioned Krylov subspace method, where the preconditioner involves the multigrid solution of a heavily damped wave equation. Here, we generalize this idea to the isotropic elastic wave equation in the frequency domain.
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