The Study On Water Flooding In NanShi Block Of SaNan Qilfield,Daqing

After more than 40 years of development,Nanshi block of Sanan Oilfield in Daqing has been in the period of ultra-high water cut,with high water cut,high recovery and highly scattered remaining oil.Three well pattern infilling adjustments have been implemented in Nanshi block.Cumulative oil production 2106 × At the present stage,the comprehensive water cut of production wells has reached 92.56%,the recovery rate is 56.14%,and the remaining oil potential is huge.At the present development stage,how to tap the potential of all kinds of oil layers and improve the production degree of oil layers is the main problem to be solved in order to realize the sustainable and stable production of water flooding in ultra-high water cut stage.With the increase of water cut,the distribution of remaining oil has changed greatly,from continuous distribution to highly dispersed distribution.Therefore,a more accurate reservoir description method is needed.First of all,the method of well seismic combined with hierarchical fine reservoir description in Nanshi block is established,which makes a breakthrough in small fault interpretation,single sand body identification and spatial quantitative characterization of remaining oil.The three-dimensional geological model of block stratum is established,and the remaining oil distribution is studied from multiple angles,and the remaining oil distribution model is established.Secondly,through coordinated reorganization of well pattern,adjustment of injection production system,subdivision of water injection and measures transformation,A set of quantitative evaluation and fine adjustment technology for injection production relationship in heterogeneous multi-layer sandstone oilfield at ultra-high water cut stage is established,so as to control production decline and water cut rise,adjust block pressure system,increase recoverable reserves and improve water drive recovery.Thirdly,fine injection production structure adjustment technology suitable for different types of remaining oil distribution characteristics is developed to broaden the space for tapping potential.Develop and perfect fine injection production structure adjustment technology,quantify subdivision water injection standard,innovate and integrate subdivision water injection and potential tapping matching technology,and alleviate the three contradictions.Finally,through research and field practice,the goal of "no decline in production and no increase in water cut in the south 10 block of Sanan Oilfield in three years,and a significant slowdown in production decline and water cut increase in peripheral blocks" has been achieved,which has greatly promoted the overall development level of Sanan Oilfield.A new way to improve the development effect in the period of ultra-high water cut is explored,which can be used for reference in the water drive development of multi-layer sandstone oilfield.