用位移势能外推法进行叠前弹性偏移是一种混合的、系统的、功能块的矢量波场偏移算法。根据位移→势能→势能外推→位移这一顺序,本文提出一种新的不均匀介质波场外推法,它相对比较精确,且不费机时。利用一种改进的适用于复杂构造的褶积声波正演模拟程序计算二种直接下行P波和S波的旅行时,这种P波和S波在弹性偏移中是必需的。本文提出一种基于时间一致原理的新的成像条件 把外推和分解后的PP波和SS波位移振幅与成像条件部面相乘就可得到二种图像(PP波和SS波)。成像条件剖面中各种波之间的串扰最小。与以前的方法相比,新提出的成像条件公式更加优越,这是因为它能用于纵横波联合震源产生的多分量地震数据的偏移。数值试验的结果是非常鼓舞人心的,它清楚地表明这种技术是可靠的。为了解决成像条件中射线的角度和极性问题,还需开展进一步的工作 Prestack elastic excursion using extrapolation of displacement potential energy is a hybrid, systematic, functional block vector wavefield migration algorithm. According to the sequence of displacement → potential energy → potential energy extrapolation → displacement, a new extrapolation method of inhomogeneous medium wavefield is proposed in this paper, which is relatively accurate and does not cost much time. This P-wave and S-wave are necessary for elastic migration when using an improved convolutional acoustic forward modeling program for complex structures to calculate two direct descending P-wave and S-wave travels. In this paper, we propose a new imaging condition based on the time-consistent principle. Two kinds of images (PP and SS waves) are obtained by multiplying the extrapolated and decomposed PP and SS wave amplitudes with the imaging conditions. Crosstalk among the various waves in the imaging condition profile is the smallest. Compared with the previous method, the newly proposed imaging condition formula is more superior because it can be used to offset the multi-component seismic data generated by the combined wave source and the S-wave. The results of the numerical experiments are very encouraging and it clearly shows that this technique is reliable. Further work is needed to address the angle and polarity of the rays in imaging conditions