The Ordovician Yijianfang carbonate reservoirs in southern Tahe oilfield are characterized by thin oil layer

complicated oil-water contact and control of fault on reservoir and hydrocarbon accumulation.The accuracy of seismic fault detection determines the accuracy of prediction of fault-controlled reservoir and the effects of exploration and deve-lopment.Based on the new reacquired high quality 3D seismic data

the Eigen coherent and ant tracking techniques are applied to detect faults on the south slope.The results of detection are combined with seismic profiles to perform fine interpretation of faults.The interpreted plane fault polygon is overlaid over the amplitude variation rate map from carbonate reservoir prediction to perform prediction of fault-controlled reservoirs.Two types of hydrocarbon enrichment patterns associated with fault are identified in the southern Tahe oilfield

namely major fault up-dip sealing type and branch fault up-dip sealing type.Exploration and development programs deployed according to these two patterns are successfully.