Kirchhoff积分法叠前时间偏移技术在三江盆地XDLZ地区的应用

三江盆地前进坳陷XDLZ地区构造较复杂，以往开展的二维叠后时间偏移成像精度低和空间位置不够准确，为此进行了二维叠前时间偏移处理研究，分析了Kirchhoff积分法叠前时间偏移处理中关键环节技术参数（叠前去噪、振幅补偿、反褶积、静校正、均方根速度建模和偏移孔径选取）对研究区复杂构造成像的影响及处理技巧。通过叠前时间偏移和叠后时间偏移在该区的应用效果对比分析，Kirchhoff积分法叠前时间偏移处理结果包含地震信息更加丰富，深层复杂构造成像在同相轴的连续性和断层及断点空间位置更趋合理，成像相位和振幅误差较小，构造成图精度提高了约4％。

Application of Kirchhoff integral method prestack time migration technique in XDLZ area of Sanjiang Basin

There exist complex structures in XDLZ area of Qianjin sag of Sanjiang Basin. The former imaging accuracy and space-location of 2D poststack time migration were not accurate. The authors did research on 2D prestack time migration processing and analyzed the key technical parameters in the Kirchhoff integral method prestack time migration process such as prestack noise attenuation, amplitude compensation, deconvolution, static correction, root-mean-square velocity model building and choosing migration aperture to the influence on the complex structure imaging in study area. compared and analyzed the application effects of the prestack and poststack time migrations in this area, the result shows that the Kirchhoff integral method prestack time migration process has more abundant seismic information; the deep complicated structure imaging is more rational in the field of the seismic event continuity and the space-location of faults and their points with less errors in its phase and amplitude; the accuracy for mapping structure is improved by ca. 4 %.