Research on RTM and Kirchhoff Migration Gathering

Common Imaging gather(CIG) can be used to velocity modeling, migration quality control, subsurface attribute interpretation and so on. Prestack AVO inversion is valuable for reservoir characterization, fracture prediction and fluid detection on complicate carbonate reservoir. However, the accuracy of AVO inversion relies on the amplitude information of CIG to a large extent. Therefore, Prestack migration should not only image reflectors correctly but also preserve the amplitude of CIG, which is the input data of AVO/AVA inversion. In this paper, we analyze the amplitude-preserved extent and adaptability on complicate structure imaging of the two imaging methods. The test results show that both RTM(Reverse Time Migration) and Kirchhoff migration are of high amplitude preservation on plain structure, and RTM are better amplitude-preserved and imaging accuracy than Kirchhoff migration on complicate structure.