The Research Of Utilization Status And Measures For The Thin And Poor Reservoir In High Water Cut Stage

After 60 years of exploration and development,the main reservoirs of Daqing Oilfield have entered high water cut stage and the distribution of residual oil is scattered.It is difficult to increase oil and control water,so in order to maintain high and stable production of oilfields,the development of thin and poor reservoirs must be strengthened.In order to improve the utilization of thin and poor reservoirs,encryption adjustment has been carried out in some oil areas,shooting thin layer and untabulated reservoirs.However,affecting by interlayer heterogeneity,poor reservoir physical properties and large injection-production well spacing,thin and poor reservoirs don't reach the production requirements.Thus,in order to improving the utilization of thin and poor reservoir,it is necessary to point at the characteristics of thin and poor reservoirs to conducted research of utilization status and measures.The study has an important significance.In the paper,based on core well data and injection profile data and dynamic and static field data,evaluating the utilization status of thin and poor reservoirs,and giving the effective utilization limit.The distribution of remaining oil in the test area is analyzed by professional software.Research shows that the proportion of medium and strong water washing in thin layer and untabulated reservoirs is less than 50% and 25%.In order to strengthen thin and poor reservoir development,permeability gradation should less than 8,and variation coefficients should less than 0.6,and sandstone layer should less than 8,and sandstone thickness should less than 6m.Main types of macro remaining oil in thin and poor reservoir are injection-production imperfection type,and stagnant zone type,and interlayer interference type.On this basis,combining the analysis on the mechanism of utilization measures,and the comparison of development effect between basic development scheme and four adjustment schemes,separate layer waterflooding technology and fracturing technology are the most effective measure to improve the utilization of thin and poor reservoir in high water cut stage.And determining the production well group corresponding fracturing is the best way to develop thin and poor reservoirs.