Polarization filtering in VSP floating coordinate system
Cui Ru-guo1,4, Mu Feng-ming2, Song Wei-qi3, Wang Cheng-li2
1. China University of Petroleum (Beijing),Beijing City 102249,China;
2. Geophysical Exploration Company,Shengli Oilfield,Dongying City,Shandong Province 257100,China;
3. China University of Petroleum (East China),Dongying City,Shandong Province 257061,China
Abstract:Polarization filtering is one of the most commonly used filtering methods for 3 component VSP PP-PS wave field separation.For traditional polarization filtering methods,calculation of the polarization angle is determined by the propagation direction of the direct wave,not the necessary upgoing wave.In this paper the polarization angle is calculated along the major energy direction of the reflection wave,and the coordinate system which varies with reflection depth,this is,the floating coordinate system,is then established,as a result the accuracy of the wave field separation is raised.Theoretical model trial calculation and data processing results show that the polarization filtering method in floating coordinate system is based on necessary wave field and can realize the optimum wave field separation.