Abstract:Relation between formations at two sides of a fault plane directly influencesboth the sealing characteristics of fault plane and the hydrocarbon acc umulation.The sealing characteristics of fault plane can be known by analysing 3-D seismic data.The technique involves the following points: •Locate fault planes by correctly interpreting both the vertical sections and horizontal slices of 3-D seismic data. •Project the fault plane in vertical and horizontal directions to obtain the amplitude sections and amplitude slices of upthrown and downthrown sides of each fault. •Achieve the lithologic interpretation of the amplitude sections and amplitude slices,by comprehensively analysing drilling data and synthetic seismograms,to have the corresponding lithologic sections and lithologic slices. •Superpose the lithologic sections of the upthrown and downthrown sides of each fault plane to get the sections that show the sealing characteristics of fault plane. The technique has brought satisfactory geology effect in esearching into the sealing characteristics of fault planes in the faulted zone of Zhangdian oil field in Nanyang depression.