Research On Seepage Law And Residual Oil Distribution At Medium-High Water Cut Period In Low- Medium Permeability Reservoir Of Matouzhuang Oilfield

After nearly twenty years of development,the production of low permeability reservoir in Fault-block Z2 in Matouzhuang Oilfield began to decline in 2008. Water cut rises up and the residual oil distribution is highly dispersed. At the same time, water flooding process has many problems and it is difficult to keep stable production. So it is urgent to adjust development plan with pertinency and applicability.First of all, the paper presents a comprehensive analysis of prominent contradictions and difficult problem to be solved of Matouzhuang Oilfield in the medium-high water cut period. Then, on the basis of comprehensive analysis of reservoir development dynamic, we carry out the research of water flooding, channeling flow distribution and reservoir composite seepage law in the target block. Finally, we study the law of residual oil distribution by a numerical simulation method and point out the potencial advantage filed.In view of the impact of channeling path during middle-high water cut period, the paper has carried on the beneficial discussion on the channeling path discriminant, seepage law research method, data processing and the description of the remaining oil and so on and makes thorough analysis of the complex seepage rule. The research has certain innovative and practical meaning.Thesis study suggests that if the low permeability reservoir wants to achieve good effect of water flooding, interlayer permeability differential should be controlled within 5.0. Using JIA model of water flooding characteristic curve, we predict the final recovery efficiency is 36.98%. By comprehensive evaluation, while maintaining the current well network condition and invariable horizon, the next best solution is to improve the injection-production ratio and the liquid withdrawal speed. The result is that the reasonable injection-production ratio is 1.0 and the reasonable fluid withdrawal rate is 3.6%. We predict that when water cut reaches 95%, the recovery degree is up to 32.1%.