Abstract：With the wide application of wide azimuth and full azimuth acquisition,long offset data is more and more used in seismic data processing. However medium anisotropy tends to have larger influence on long offset data,which results in decreasing imaging accuracy. In addition,anisotropic migration algorithms have been rapidly developed,but anisotropic parameter modeling is still relatively lagged behind. Therefore we propose in this paper an anisotropic parameter tomography inversion. First using P-SV wave separation as raytracing,we provide accurate information such as travel time and ray path for tomography inversion. Then we conduct simultaneous iterative reconstruction (SIR) by deducing tomographic matrix of VTI medium. Finally we focus on the sensitivity of three anisotropy parameters on different angles in VTI medium,and perform a sequential inversion of the parameters based on angle constraint. Model trial and real data processing results show that the proposed approach puts imaging depth to the real position,and improves imaging compatibility with well data,and adapt well to complex structures.
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