Structure-preserving numerical simulation for Earth's free oscillations

doi:10.6038/cjg20160513

CORC > 地质与地球物理研究所 > 中国科学院地质与地球物理研究所 > 中国科学院地球与行星物理重点实验室

	Structure-preserving numerical simulation for Earth's free oscillations
	Chen Shi-Zhong 1,2,3; Li Xiao-Fan 1; Wang Wen-Shuai 4
刊名	CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
	2016-05-01
卷号	59 期号:5 页码:1685-1695
关键词	Earth's free oscillations Structure-preserving simulation Long-term tracing Three-order symplectical spectral element method
DOI	10.6038/cjg20160513
文献子类	Article
英文摘要	Free oscillations of the Earth are usually as standing waves of entire globe, which can be excited by many factors such as a great earthquake. The oscillation types of this physical phenomenon depend on Earth's structure and physical parameters. Therefore, intrinsic characters of the Earth can be revealed by studying Earth' free oscillations. Numerical simulation is an effective way to research seismic waves travelling in different earth models. In essence, the numerical simulation of Earth's free oscillations is a long-term tracing of variable coefficient wave equation. The majority of numerical methods for seismic wave simulation are non-structure preserving methods, which cannot suppress the accumulative error in long-time computation, e.g., finite difference methods, pseudo-spectral methods, and finite element methods. In comparison, the symplectical methods based on the Hamilton system possess fine structure preserving ability which makes them be suitable for the physical problem acquiring good precision in long-time simulation. The spectral element method combines the generality of the finite element method with the accuracy of spectral techniques. This method expands the solution in trigonometric series, of which a chief advantage is that the resulting method is of very high order. It also chooses high-degree piecewise polynomial basis functions, also achieving a very high order of accuracy. Symplectical methods introduced into spectral element methods may be an accurate and effective choice. In this research, a three-order symplectical spectral element method is modified for long-time simulation of Earth's free oscillations and seismic waves propagating in the global range. The event simulated is a great earthquake (M(s)8.6) off the west coast of northern Sumatra on 11 April 2012. The PREM earth model is used for simulation. Our method and traditional spectrum element method using Newmark time scheme are chosen for simulation respectively with the same parameters and computation scales. The time step adopted by our method is 2.8 times that adopted by the Newmark method. Even under this extreme condition, the feasibility and effectiveness of this method have been proved by analysis of the simulation results, especially, by comparing with real seismic data processed with the same procedures and parameters. Those data are provided by the Incorporated Research Institutions for Seismology. This improvement can be a new and valid alternative to numerical methods for investigation on heterogeneity (especially lateral heterogeneity) in the globe range. Meanwhile, Earth's free oscillations influenced obviously by large in-homogeneous structure of Earth interiors has been confirmed by comparison of simulation results and real seismic data recorded by seismic networks.
WOS关键词	SEISMIC-WAVE PROPAGATION ; SPECTRAL ELEMENT METHOD ; MODEL ; EARTHQUAKE
WOS研究方向	Geochemistry & Geophysics
语种	英语
WOS记录号	WOS:000375637700013
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/53500]
专题	地质与地球物理研究所_中国科学院地球与行星物理重点实验室
作者单位	1.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Earth & Planetary Phys, Beijing 100029, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.North China Univ Water Resources & Elect Power, Sch Resources & Environm, Zhengzhou 450045, Peoples R China 4.Ningxia Univ, Sch Math & Comp Sci, Yinchuan 750021, Peoples R China
推荐引用方式 GB/T 7714	Chen Shi-Zhong,Li Xiao-Fan,Wang Wen-Shuai. Structure-preserving numerical simulation for Earth's free oscillations[J]. CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,2016,59(5):1685-1695.
APA	Chen Shi-Zhong,Li Xiao-Fan,&Wang Wen-Shuai.(2016).Structure-preserving numerical simulation for Earth's free oscillations.CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION,59(5),1685-1695.
MLA	Chen Shi-Zhong,et al."Structure-preserving numerical simulation for Earth's free oscillations".CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION 59.5(2016):1685-1695.