[an error occurred while processing this directive] Global Geology 2017, 20(3) 184-190 DOI:   10.3969/j.issn.1673-9736.2017.03.07  ISSN: 1673-9736 CN: 22-1371/P
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wavefield decomposition
reverse-time migration
multiple wave components
imaging condition
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GONG Qiming
HAN Liguo
ZHOU Jinju
PubMed
Article by Gong Q
Article by Han L
Article by Zhou J
Elastic reverse time migration based on vector wavefield decomposition
GONG Qiming, HAN Liguo, ZHOU Jinju
College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China
ժҪ�� Prestack elastic reverse time migration (RTM) requires multicomponent seismic data. But for multicomponent elastic Kirchhoff migration, there is a limitation that ray theory no longer applies if thegeology becomes complicated.In this paper, the authors have created a new 2D migration context for isotropic, elastic RTM, which included decomposition of the elastic source and receiver wavefields into P and S wave vectors by decoupled elastodynamic extrapolation, which retained the same stress and particle velocity components as the input data. Then we appliedsource-normalized crosscorrelation imaging condition in elastic reverse time migration to compensate the energy of deep strata. We found that the resulting images were nearly identical to the velocity model, and the resolution has been improved. Our method is a wavefielddecomposition based on vector, and we can alsoavoid the problem of polarity reversal of converted shear wave imaging. It proved the applicability of the method proposed in our paper.
�ؼ����� wavefield decomposition   reverse-time migration   multiple wave components   imaging condition  
Elastic reverse time migration based on vector wavefield decomposition
GONG Qiming, HAN Liguo, ZHOU Jinju
College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China
Abstract: Prestack elastic reverse time migration (RTM) requires multicomponent seismic data. But for multicomponent elastic Kirchhoff migration, there is a limitation that ray theory no longer applies if thegeology becomes complicated.In this paper, the authors have created a new 2D migration context for isotropic, elastic RTM, which included decomposition of the elastic source and receiver wavefields into P and S wave vectors by decoupled elastodynamic extrapolation, which retained the same stress and particle velocity components as the input data. Then we appliedsource-normalized crosscorrelation imaging condition in elastic reverse time migration to compensate the energy of deep strata. We found that the resulting images were nearly identical to the velocity model, and the resolution has been improved. Our method is a wavefielddecomposition based on vector, and we can alsoavoid the problem of polarity reversal of converted shear wave imaging. It proved the applicability of the method proposed in our paper.
Keywords: wavefield decomposition   reverse-time migration   multiple wave components   imaging condition  
�ո����� 2016-12-28 �޻����� 2017-04-13 ����淢������  
DOI: 10.3969/j.issn.1673-9736.2017.03.07
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Supported by the National"863" Project(No.2014AA06A605)

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