2D and 3D elastic wavefield vector decomposition in the wavenumber domain for VTI media
2D and 3D elastic wavefield vector decomposition in the wavenumber domain for VTI media
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DOI：
10.1190/1.3431045
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发表时间：
2010-06
期刊：
影响因子：
3.3
通讯作者：
Qunshan Zhang;G. McMechan
中科院分区：
文献类型：
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作者：
Qunshan Zhang;G. McMechan
将矢量波场分解为P波和S波的实用方法是基于亥姆霍兹理论和克里斯托弗方程。它适用于平面波极化在给定波数附近连续且由该波数唯一定义的VTI介质，但VTI对称轴上的KISS奇点除外。与将波场分为标量场和矢量场的散度和旋度不同，分解后的P波场和S波场都是矢量场，具有正确的幅度、相位和物理单位。如果将分解后的波场的矢量分量相加，它们将重构原始输入波场的矢量分量。在波数域中具有相同极化分布(即相同的特征向量)的VTI介质的任何部分中，波场的传播具有相同的分解算符，并且可以用每个算符(例如，一个用于P波和一个用于S波)的单个三维傅立叶变换来重建。这适用于各向同性波场和各向同性波场。
A pragmatic decomposition of a vector wavefield into P- and S-waves is based on the Helmholtz theory and the Christoffel equation. It is applicable to VTI media when the plane-wave polarization is continuous in the vicinity of a given wavenumber and is uniquely defined by that wavenumber, except for the kiss singularities on the VTI symmetry axis. Unlike divergence and curl, which separate the wavefield into a scalar and a vector field, the decomposed P- and S-wavefields are both vector fields, with correct amplitude, phase, and physical units. If the vector components of decomposed wavefields are added, they reconstruct those of the original input wavefield. Wavefield propagation in any portions of a VTI medium that have the same polarization distribution (i.e., the same eigenvector) in the wavenumber domain have the same decomposition operators and can be recon-structed with a single 3D Fourier transform for each operator (e.g., one for P-waves and one for S-waves).This applies to isotropic wavefields a...