Abstract：Two-step separation was conducted for anisotropy vector wavefield.The first step is to make the anisotropic elastic wave equation in the polarization direction of the projection isotropic so that it has clear and intuitive kinematic and dynamic characteristics;the second step is to calculate anisotropic medium propagator wavefield separation waveform correction based on the correction of the projected direction of the wavefield in the isotropic direction back to the anisotropic direction, and ultimately the anisotropic wavefield separation can be achieved.First of all,the test of VTI media proves its feasibility.In addition,the authors put forward the surface data decomposition,namely,data decomposition is conducted for collected multicomponent seismic data before the migration imaging.In order to get the pure qP wave,qSH wave and qSV wave data the authors conducted the surface data input control to obtain the satisfactory imaging results of components and make imaging decomposition of the surface data performed in a controlled process,thus reducing unnecessary computation.The authors conducted decomposition of Hess forward modeling shot record data and reverse-time migration imaging.
任丽娟, 李振春, 王延光, 刘兴达, 孙小东. 基于矢量波场分离的TI介质逆时偏移[J]. 物探与化探, 2015, 39(1): 196-202.
REN Li-Juan, LI Zhen-Chun, WANG Yan-Guang, LIU Xing-Da, SUN Xiao-Dong. Reverse-time migration for TI medium based on vector wavefield separation. Geophysical and Geochemical Exploration, 2015, 39(1): 196-202.
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