False structures on time domain seismic sections and corresponding resolutions
Chen Hai-qing1,2, Dai Xiao-yun2, Pan Liang-yun2, Zhao Ye-Ping2, He Li-hong2, Chen Yuan-zhong2, He Bao-wei2, Wang Yun-bo2, Tan Su-hua2
1. Ocean University of China,Qindao City,Shandong Province,266100,China;
2. Geophysical Research Institute of BGP Inc.,CNPC,Zhuozhou City,Hebei Province,072751,China
Abstract：False structure(or structure high point migration) on seismic sections is a problem which always perplexes the seismic interpreters.In this paper the authors conducted several case studies and believed that the false structure(or structure high point migration) always exist on seismic sections in some certain circumstances,for example,when salt domes,regional igneous bodies,lower blocks of reverse fault,steep upper layers or rapid thickness change of upper layer exist in upper layer,the false structure can often be found in the lower layers.As the false structures always exist on seismic sections and they are hardly avoided in seismic data processing,the authors believe that the pre-stack depth migration(PSDM) is an ideal tool to solve the problem,however in some circumstances where PSDM can not be done,the authors then suggest to try to obtain best possible processing results through variable velocity time-depth conversion which is based on the accurate velocity field.
