The Changqing Special Low Permeability Reservoirs Leading Injection Mechanism And Improve Performance

As the continual enhance of technique for the exploration and the oil layer reconstruction, making a general survey of the development strategy of energy source of china, the exploration of low-permeability oil field and extreme-low-permeability oil field has become the important potential of the steady development of onshore oil industry in china, and such exploration will be the technique direction of sustainable development of oil industry in future. Taking the Changqing oil field for example, the extreme-low-permeability oil reservoir has account for 61% of the produced reserves, and its output accounts for 54.4% of yearly oil production. These low-permeability reserves have the characteristics of the wide acreage, the great reserves, the low abundance, the bad properties and the great development difficulty. At present about 50% of these reserves are not put into exploitationDirect towards the traits that the percolation of fluid in the low-permeability oil layer is non-Darcy flow with star-up pressure gradient and the oil formation bears elastic-plastic deformation, Changqing oil field brings forward an efficient water injection mode—advanced water injection, which can improve the effect of oil field exploration through the extended search of exploration mode in reason. But the researches based on the mechanism of advanced water injection improving the effect of exploration and the development technique policy of advanced water injection are few. So, on the base of studying the WuLiwan No.1 block and Dongzhi block reservoir in Changqing oil field, this paper researches on the mechanism of advanced water injection improving the effect of exploration, and is significant in bothaspects of theory and practice.On the basis of studying the extreme-low-permeability geologic features and exploitation dynamic characteristics of the extreme-low-permeability reservoir in Changqing oil field, this paper has completed the following research work and gained the relevant research achievements: Geology trait evaluation of the research area has been achieved with the applying of reservoir geology and reservoir engineering method; The methods such as percolation mechanics, reservoir engineering and simulation experiment have been employed to analyze the percolation mechanism of the extreme-low-permeability reservoir in Changqing oil field and establish the stable water injection percolation theory of reservoir considering the start-up pressure gradient; The methods, achieved by the intersection and infiltration of percolation mechanics, reservoir engineering and modern computing technology have been applied to analyze the mechanism of advanced water injection mode improving the effect of exploration, and establish the advanced water injection percolation theory of the extreme-low-permeability reservoir considering the start-up pressure gradient; Reservoir geology modeling technique has been employed to establish quantitative geologic...