Publikationsdatum:
2016-10-29
Beschreibung:
We present a new, computationally efficient numerical method to simulate global seismic wave propagation in realistic 3-D Earth models. We characterize the azimuthal dependence of 3-D wavefields in terms of Fourier series, such that the 3-D equations of motion reduce to an algebraic system of coupled 2-D meridian equations, which is then solved by a 2-D spectral element method (SEM). Computational efficiency of such a hybrid method stems from lateral smoothness of 3-D Earth models and axial singularity of seismic point sources, which jointly confine the Fourier modes of wavefields to a few lower orders. We show novel benchmarks for global wave solutions in 3-D structures between our method and an independent, fully discretized 3-D SEM with remarkable agreement. Performance comparisons are carried out on three state-of-the-art tomography models, with seismic period ranging from 34 s down to 11 s. It turns out that our method has run up to two orders of magnitude faster than the 3-D SEM, featured by a computational advantage expanding with seismic frequency.
Schlagwort(e):
Geodynamics and Tectonics
Print ISSN:
0956-540X
Digitale ISSN:
1365-246X
Thema:
Geologie und Paläontologie
Publiziert von
Oxford University Press
im Namen von
The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
