The Oil Remaining Distribution Study On Gaotaizi Reservoir In Developed Area Of Yingtai Oilfield

After20years of development, Gaotaizi reservoir entered the ultra high water cut period, resulting in aseries of complicated problems, such as indefinite layering production circumstance, uncertain residual oilpotentials, high reserve recovery degree, serious edge-bottom water breakthrough and unclear residual oildistribution.Aiming at these problems, the development effect evaluation and the study on residual oil distributionwere conducted.The3-D geological model which made small layer as unit was established. Based onproduction history, the production stage division and production features study were conducted. Thesingle-layer production division was conducted.The changing rules of edge-bottom water was studied, andthe natural water flooding development effect was evaluated. The repeated reserves calculation and theresidual oil potentials analysis were conducted.Under the circumstances of lacking of oil testing data, water flushing circumstances data of coringwell and performance monitoring data, the representative main reservoir was selected for production rulesstudy and changing rules study on edge-bottom water, then generalized them in each small layer. Theresidual oil of non-main reservoir was distributed near high point of local structure. The residual oilresulted from lithologic changes was little. The development practice proved that the east and west partshad the same oil-bearing performance, so the poor-developed small layer in east part was the mainpotentials tapping area.