Analysis Of Productivity And Pressure Response Of Complex Hydraulic Fracture Networks In Tight Oil Reservoirs

In recent years,tight oil has been paid much more attention than before,for ordinary reservoirs are less and less.Now multi-fractured horizontal wells are mainly used to develop tight oil both in China and overseas.While producing hydraulic fractures,volume fracturing technology make natural fractures in the reservoir grow.Along with natural fractures,hydraulic fractures become into fracture networks.Therefore,it is very important to analyse productivity and pressure response of complex hydraulic fracture networks.In this paper,a semi-analytical model is built to analyze the productivity and pressure response of hydraulic fracturing horizontal well with complex fracture networks in tight oil reservoir.The redistribution of oil flow in the intersection of fracture in the complex fracture network is considered.The results demonstrate that the more complex the fracture networks are,the more the intersection fractures are,the less the fracture interval is,the earlier the radial flow appears,the more obvious bilinear flow is,and the longer the bilinear lasts for.The effect of the closed fractures after hydraulic fracturing treatment on the productivity of horizontal wells is analyzed for the first time.The location and amount of the ineffective fractures is different,the productivity of the horizontal well is different.The effectiveness of hydraulic fractures can be verified by the analysis of productivity and bottom hole pressure response of horizontal wells.The analysis can help to improve the design and treatment of hydraulic fracturing in tight reservoirs.