An Initial Study of the Numerical Simulation of the Earth′s Free Oscillations Process Excited by Earthquake
Received date: 2008-05-30
Revised date: 2008-08-21
Online published: 2008-10-10
The eigenfrequencies of the Earth′s free oscillations are closely related to the Earth′s internal structures. Elaborately investigating the characteristics of the Earth′s free oscillations can open another window to address the hierarchical structures with variations of this mysterious planet on which we are living. The traditional method mainly focused on calculating the eigenfrequencies by analytical ways, whereas it lacks the advantage of modeling a realistic earth model with lateral heterogeneity, from studying on the process from earthquake occurrence to the Earth′s free oscillations inspired. We proposed numerical simulation method which is based on the elastic propagation theory; the spectral element method and high performance parallel computing were incorporated to simulate the seismic wave propagation process in the Earth's interior. As a preliminary study, we neglected the effects of the Earth′s gravitational potential. The seismographic data recorded by synthetic stations were analyzed by power spectral density distribution analysis, and compared with those from the theoretical values of PREM model. We found that the simulated results of toroidal modes agreed well with the theoretical values.
ZHANG Huai , SHI Yaolin , YANG Changchun , YAN Zhenzhen . An Initial Study of the Numerical Simulation of the Earth′s Free Oscillations Process Excited by Earthquake[J]. Advances in Earth Science, 2008 , 23(10) : 1020 -1026 . DOI: 10.11867/j.issn.1001-8166.2008.10.1020
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