Elastic reverse-time migration based on amplitude-preserving P- and S-wave separation
Yang Jia-Jia1,2, Luan Xi-Wu1,2, Fang Gang1,2, Liu Xin-Xin1,2, Pan Jun1,2, and Wang Xiao-Jie1,2
1. Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology, Ministry of Land and Resources, Qingdao Institute of Marine Geology, Qingdao 266071, China;
2. Laboratory for Marine Mineral Resources, National Laboratory for Marine Science and Technology, Qingdao 266071, China.
Abstract：
Imaging the PP- and PS-wave for the elastic vector wave reverse-time migration requires separating the P- and S-waves during the wave field extrapolation. The amplitude and phase of the P- and S-waves are distorted when divergence and curl operators are used to separate the P- and S-waves. We present a P- and S-wave amplitude-preserving separation algorithm for the elastic wavefield extrapolation. First, we add the P-wave pressure and P-wave vibration velocity equation to the conventional elastic wave equation to decompose the P- and S-wave vectors. Then, we synthesize the scalar P- and S-wave from the vector P- and S-wave to obtain the scalar P- and S-wave. The amplitude-preserved separated P- and S-waves are imaged based on the vector wave reverse-time migration (RTM). This method ensures that the amplitude and phase of the separated P- and S-wave remain unchanged compared with the divergence and curl operators. In addition, after decomposition, the P-wave pressure and vibration velocity can be used to suppress the interlayer reflection noise and to correct the S-wave polarity. This improves the image quality of P- and S-wave in multicomponent seismic data and the true-amplitude elastic reverse time migration used in prestack inversion.
. Elastic reverse-time migration based on amplitude-preserving P- and S-wave separation[J]. APPLIED GEOPHYSICS, 2016, 13(3): 500-510.
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2016, Vol. 13 
