Caved carbonate reservoir prediction based on AVO inversion
Zhang Yuanyin1, Sun Zandong1, Tang Zhiyuan1, Li Yingwei1,2
1. Lab for Integration of Geology and Geophysics,State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;
2. Research Institute of Shenzhen Branch,CNOOC,Guangzhou,Guangdong 510240,China
Abstract:Conventional methods are used for caved car-bonate reservoir prediction on bead-like strong re-Elections of post-stack section in the Tarim Basin.However, the filling substances of caves cannot bedistinguished,and the internal weak impedancereservoir without bead-like reflection is also neg-lected using these conventional methods.Based on seismic amplitude-preserved processing and rockphysics analysis,pre-stack inversion is employed inthis paper for caved carbonate reservoir predictionin Wells TZ45,ZU21 and LU34 zones.Comparingwith conventional post-stack methods,AVO inver-lion can not only distinguish resolvable dissolutioncaves, but also predict the filling substances. Mo-reover, it can characterize the distribution of inter-nal weak impedance reservoir without bead-like re-Election. In practice,the coincidence of AVO in-version prediction with the drilling results of 33wells in the zones is up to 91.3%.