Pseudo-Acoustic Wave Rquations for Reverse-Time Migration in TI Media

详细信息   

• 责任者：Kang Wei (Key Laboratory of Marine Geology ; School of Ocean and Earth Science ; Tongji University ; Shanghai 200092 ; China) ; Cheng Jiubing
• 刊名：Chinese Journal of Geophysics
• 出版年：2012
• 卷期：55(3)
• 关键词：时间偏移 ; time migration ; 波动方程 ; wave equation
• 页码：p.1033-1045
• 图表：6 illus., 36 tables, 1 ref.
• 分类号：1600
• issnNo：ISSN0001-5733
• isbnNo：CN11-2074/P

摘要

Neglecting anisotropy in seismic imaging may result in remarkable positional errors and focusing problem,especially for long-offset, wide azimuth seismic data. In this paper, starting from elastic wave equations in VTI media,we present new pseudo-acoustic wave equations and the corresponding expression for qP wave. The equations expressed by wavefield and expressed by stress indicate the physical meaning of second-order coupled equations derived from the dispersion relationship. Then, the authros extend the pseudo-acoustic wave equations to TTI media by tilting the coordinate system. The authors show numerical examples to demonstrate that acoustic approximation equations save much computational cost in VTI media. Testing result of reverse-time migration with the SEG/HESS model and overthrust model validated these equations.