Study on Optimization of Combined Parameters of Subdivision Water Injection Layer Sections in Ultra-high Water Cut Stage

Abstract

After 50 years of exploitation, Block A has entered the development stage of the ultra-high water cut stage. Although the layer series of development has been subdivided and adjusted, the interlayer interference is still serious, imposing difficulties in development adjustment. Based on dynamic production data and monitoring data analysis, this paper applies multi-disciplinary reservoir description technology and introduces economic evaluation indicators to quantitatively analyze the variation coefficient of permeability within subdivided layer sections, the number of monolayer breakthrough series and sections, the number of small layers within a layer section, and the effect of sandstone thickness on the subdivision and adjustment effect, analyze the influence of well test period and operation costs on the economic benefits, and the optimize combined parameters of subdivision water injection layer sections. After field application, the utilization proportion of sandstone in the soil layer with the subdivided well permeability of less than 0.1 μ m2 increased by 18.3 percentage points, and the average daily oil output per well in the surrounding wells increased by 0.3 t, effectively reducing the decline in output and increase in the water cut, and providing technical support for water flood fine potential tapping in the ultra-high water cut stage.