Water Plugging& Profile Control Technologies And Profile Optimization Scheme Study Of Pu Ⅰ Formation In North Transition Belt Of Daqing Oilfield

The North Development Zone is the first industrial block of polymer flooding in the transitional zone of Daqing Oilfield.Owing to the development gap between the transitional zone oil reservoir and the pure oil zone,the nature of the crude oil is quite different from that of the pure oil zone.Therefore,during the profile adjustment process,the dynamic reflection of the production well is somewhat different from that of the pure oil zone.In addition,the transition zone is currently in the late stage of high water content,which is also different from the test area.With the continuous rise of the water content in the oil field and the the number of casing damage well increasing year by year,mechanical subdivision injection can hardly fully meet the needs of adjusting and tapping potential of oil fields.From the dynamic reflection of industrialized polymer accumulation blocks,it can be seen that in spite of the significant results of most well groups,some well group are still confronted with a series of problems such as low injection pressures,poor water absorption profiles,low water cuts,low oil increase,high concentration of coal,and low accumulation ratio.Therefore,it is essential to optimize the profile adjustment plan and seriously to evaluate the effect of the transition zone.In this paper,by taking advantage of fine geological research results and borehole coring data,the sedimentary characteristics,reservoir development and remaining oil distribution types of the block were studied.The heterogeneity of the target oil layer was studied from the plane and the longitudinal direction,respectively.The flooding interpretation data and isotope test data were applied to analyze the flooding degree of the block,the extent of oil layer mobilization,and the distribution of remaining oil.Through the collection and analysis of dynamic and static data of the block,the evaluation of deep profile control experiments and the optimization study of the block profile optimization program were conducted.In-depth understanding of the development of the block to guide the production practices,to maximize the block recovery,to provide practical basis and technical support for the transition zone oil layer in the later period of high water production.