Plane-Wave Least-Squares Reverse Time Migration for Rugged Topography  

作　　者：Jianping Huang Chuang Li Rongrong Wang Qingyang Li 

机构地区：[1]School of Geosciences,China University of Petroleum (East China) [2]College of Information and Control Engineering,China University of Petroleum (East China)

出　　处：《Journal of Earth Science》2015年第4期471-480,共10页地球科学学刊（英文版）

基　　金：jointly financial support of the National 973 Project of China(Nos.2014CB239006,2011CB202402);the National Natural Science Foundation of China(Nos.41104069,41274124);the Shandong Natural Science Foundation of China(No.ZR2011DQ016);the Fundamental Research Funds for the Central Universities of China(No.R1401005A)

摘　　要：We present a method based on least-squares reverse time migration with plane-wave encoding （P-LSRTM） for rugged topography. Instead of modifying the wave field before migration, we modify the plane-wave encoding function and fill constant velocity to the area above rugged topography in the model so that P-LSRTM can be directly performed from rugged surface in the way same to shot domain reverse time migration. In order to improve efficiency and reduce I/O （input/output） cost, the dynamic en- coding strategy and hybrid encoding strategy are implemented. Numerical test on SEG rugged topography model show that P-LSRTM can suppress migration artifacts in the migration image, and compensate am- plitude in the middle-deep part efficiently. Without data correction, P-LSRTM can produce a satisfying image of near-surface if we could get an accurate near-surface velocity model. Moreover, the pre-stack P- LSRTM is more robust than conventional RTM in the presence of migration velocity errors.We present a method based on least-squares reverse time migration with plane-wave encoding （P-LSRTM） for rugged topography. Instead of modifying the wave field before migration, we modify the plane-wave encoding function and fill constant velocity to the area above rugged topography in the model so that P-LSRTM can be directly performed from rugged surface in the way same to shot domain reverse time migration. In order to improve efficiency and reduce I/O （input/output） cost, the dynamic en- coding strategy and hybrid encoding strategy are implemented. Numerical test on SEG rugged topography model show that P-LSRTM can suppress migration artifacts in the migration image, and compensate am- plitude in the middle-deep part efficiently. Without data correction, P-LSRTM can produce a satisfying image of near-surface if we could get an accurate near-surface velocity model. Moreover, the pre-stack P- LSRTM is more robust than conventional RTM in the presence of migration velocity errors.

关 键 词：least-squares migration rugged topography plane-wave encoding dynamic encoding hybrid encoding. 

分 类 号：P631.4[天文地球—地质矿产勘探]