Pure quasi-P wave equation and numerical solution in 3D TTI media
Zhang Jian-Min1,2,3, He Bing-Shou1,2,3, and Tang Huai-Gu1,2,3
1. Ocean University of China, Qingdao Shandong 266100, China.
2. Evaluation and Detection Technology Laboratory of Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
3. Key Lab of Submarine Geosciences and Prospecting Techniques Ministry of Education, Qingdao 266100, China.
Abstract：
Based on the pure quasi-P wave equation in transverse isotropic media with a vertical symmetry axis (VTI media), a quasi-P wave equation is obtained in transverse isotropic media with a tilted symmetry axis (TTI media). This is achieved using projection transformation, which rotates the direction vector in the coordinate system of observation toward the direction vector for the coordinate system in which the z-component is parallel to the symmetry axis of the TTI media. The equation has a simple form, is easily calculated, is not influenced by the pseudo-shear wave, and can be calculated reliably when δ is greater than ε. The finite difference method is used to solve the equation. In addition, a perfectly matched layer (PML) absorbing boundary condition is obtained for the equation. Theoretical analysis and numerical simulation results with forward modeling prove that the equation can accurately simulate a quasi-P wave in TTI medium.
. Pure quasi-P wave equation and numerical solution in 3D TTI media[J]. APPLIED GEOPHYSICS, 2017, 14(1): 125-132.
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2017, Vol. 14 
