1. 中国石油杭州地质研究院 浙江杭州 310023;
2. 中国石油大学（华东）地球资源与信息学院 山东青岛 266555;
3. Modeling and Imaging Laboratory University oi California Santa Cruz 95064 USA
Beamlet prestack depth migration on crosswell data
Ye Yueming1, Li Zhenchun2, Wu Rushan3, Zhuang Xijin1
1. Hangzhou Research Institute of Geology,PetroChina,Hangzhou,Zhejiang 310023,China;
2. College of Geo-resources and Information,China University of Petroleum(East China),Qingdao,Shandong 266555,China;
3. Modeling and Imaging Laboratory,University of California,Santa Cruz 95064,USA
Abstract：We can get better complex structure image from prestack depth migration of surface seismic data,but it lacks of resolution when imaging in some area with thin layers.Cross-well acquisition system has little effect from the surface and has higher frequency information,which can get higher resolution image.Prestack depth migration based on one way wave equation can adapt to area with strong velocity variation.However,this conventional migration method cannot be directly used for corsswell data.In this paper,we perform the crosswell prestack depth migration with the thought of wave field accumulation gradually based on the directly downward continuation.The beamlet migration operator was introduced which has localized reference velocity.The localized reference velocity reduces the perturbation velocity and improves the calculation accuracy.The test of complex crosswell model migration has proved the validity and effectiveness of our method.The faults are clearer and migration noise was better suppressed.
