气候变化领域集成服务门户(CCPortal): Traveltime Calculations for qP, qSV, and qSH Waves in Two-Dimensional Tilted Transversely Isotropic Media

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DOI	10.1029/2019JB018868
	Traveltime Calculations for qP, qSV, and qSH Waves in Two-Dimensional Tilted Transversely Isotropic Media
	Huang G.; Luo S.; Deng J.; Vavryčuk V.
发表日期	2020
ISSN	21699313
卷号	125 期号:8
英文摘要	This paper presents a fast sweeping method (FSM) to calculate the first-arrival traveltimes of the qP, qSV, and qSH waves in two-dimensional (2D) transversely isotropic media, whose symmetry axis may have an arbitrary orientation (tilted transverse isotropy [TTI]). The method discretizes the anisotropic eikonal equation with finite difference approximations on a rectangular mesh and solves the discretized system iteratively with the Gauss-Seidel iterations along alternating sweeping orderings. At each mesh point, a highly nonlinear equation is solved to update the numerical solution until its convergence. For solving the nonlinear equation, an interval that contains the solutions is first determined and partitioned into few subintervals such that each subinterval contains one solution; then, the false position method is applied on these subintervals to compute the solutions; after that, among all possible solutions for the discretized equation, a causality condition is imposed, and the minimum solution satisfying the causality condition is chosen to update the solution. For problems with a point-source condition, the FSM is extended for solving the anisotropic eikonal equation after a factorization technique is applied to resolve the source singularities, which yields clean first-order accuracy. When dealing with the triplication of the qSV wave, solutions corresponding to the minimal group velocity are chosen such that continuous solutions are computed. The accuracy, efficiency, and capability of the proposed method are demonstrated with numerical experiments. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	anisotropic TTI media; eikonal solver; factored eikonal equation; traveltime computation
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187734
作者单位	Department of Geophysics, East China University of Technology, Nanchang, China; Department of Mathematics, Iowa State University, Ames, IA, United States; Institute of Geophysics, The Czech Academy of Science, Praha, Czech Republic
推荐引用方式 GB/T 7714	Huang G.,Luo S.,Deng J.,et al. Traveltime Calculations for qP, qSV, and qSH Waves in Two-Dimensional Tilted Transversely Isotropic Media[J],2020,125(8).
APA	Huang G.,Luo S.,Deng J.,&Vavryčuk V..(2020).Traveltime Calculations for qP, qSV, and qSH Waves in Two-Dimensional Tilted Transversely Isotropic Media.Journal of Geophysical Research: Solid Earth,125(8).
MLA	Huang G.,et al."Traveltime Calculations for qP, qSV, and qSH Waves in Two-Dimensional Tilted Transversely Isotropic Media".Journal of Geophysical Research: Solid Earth 125.8(2020).