Multiwave velocity analysis based on Gaussian beam prestack depth migration
Han Jian-Guang1,2, Wang Yun3, Han Ning4, Xing Zhan-Tao1, and Lu Jun5
1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.
2. University of Chinese Academy of Sciences, Beijing 100049, China.
3. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
4. College of Resources and Environment, Southwest University, Chongqing 400716, China.
5. China University of Geosciences (Beijing), Beijing 100083, China.
Abstract：
Prestack depth migration of multicomponent seismic data improves the imaging accuracy of subsurface complex geological structures. An accurate velocity field is critical to accurate imaging. Gaussian beam migration was used to perform multicomponent migration velocity analysis of PP- and PS-waves. First, PP- and PS-wave Gaussian beam prestack depth migration algorithms that operate on common-offset gathers are presented to extract offset-domain common-image gathers of PP- and PS-waves. Second, based on the residual moveout equation, the migration velocity fields of P- and S-waves are updated. Depth matching is used to ensure that the depth of the target layers in the PP- and PS-wave migration profiles are consistent, and high-precision P- and S-wave velocities are obtained. Finally, synthetic and field seismic data suggest that the method can be used effectively in multiwave migration velocity analysis.
HAN Jian-Guang,WANG Bin,HAN Ning et al. Multiwave velocity analysis based on Gaussian beam prestack depth migration[J]. APPLIED GEOPHYSICS, 2014, 11(2): 186-196.
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2014, Vol. 11 
