Elastic wave propagation simulation in anisotropic media and random media using high-order difference method of rotation staggered grids based on convolutional perfectly matched layer
De-Shan FENG1,2, Xiang-Yu WANG1,2
1. School of Geosciences and Info-Physics,Central South University,Changsha 410083,China 2. Key Laboratory of Non-ferrous Resources and Geological Detection of Hunan Province,Changsha 410083,China
On the basis of the first-order velocity-stress elastic wave equation,a finite-difference discretization scheme with 2M-order accuracy of second-order space accuracy is deduced based on rotational staggered grid.The principle of recursive convolutional complex frequency shift perfectly matched layer (CPML) boundary condition is expounded,and the recurrence formula of first order velocity-stress elastic wave high order difference CPML boundary condition is established.The selection of the key parameter m,and sum of CPML boundary is carried out.By analyzing the distribution of reflection error,the optimal parameters of CPML boundary condition are selected.Both global reflection errors and wavefield snapshots indicate that CPML has better absorption properties than evanescent waves.On the basis of the Matlab platform,a program of elastic staggered forward simulation of rotating staggered grid based on CPML boundary is developed.The program is used to simulate the anisotropic medium and random medium.The seismic wave forward record and wavefield snapshot are obtained.The forward propagation profile and the wavefield snapshots can be used to better understand the propagation characteristics of seismic waves in anisotropic media and random media and to guide the interpretation of seismic exploration data in heterogeneous media.
冯德山, 王向宇. 基于卷积完全匹配层的旋转交错网格高阶差分法模拟弹性波传播[J]. 物探与化探, 2018, 42(4): 766-776.
De-Shan FENG, Xiang-Yu WANG. Elastic wave propagation simulation in anisotropic media and random media using high-order difference method of rotation staggered grids based on convolutional perfectly matched layer. Geophysical and Geochemical Exploration, 2018, 42(4): 766-776.
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