1. School of Geoscience, China University of Petroleum (East China), Qingdao, Shandong 266580, China;
2. Department of Data Processing, Exploration and Developing Institute, Liaohe Oilfield Company, PetroChina, Panjin, Liaoning 124010, China;
3. Reseanh & Development Department, BGP Inc., CNPC, Zhuozhou, Hebei 072751, China
Abstract：We base on Kirchhoff integral for propagated wavefields to realize migration, and rely on the calculation of the Green functions for the classical wave equation by performing a summation of Gaussian beams for the direct and back propagated wavefield. The subsurface image is obtained by calculating the coherence between the direct and back-propagated wavefields. The model calculation and the real data verify that our method combines the advantages of the high computational speed of ray-based migration with the high accuracy of reverse-time wave-equation migration, which can overcome problems with caustics, yield good images of steep dips, and be readily extendible to target-oriented implementation.
