Staged Fracturing Pattern and Parameter Optimization of Horizontal Wells in Tight Sandstone Oil Reservoir

In order to achieve reservoir stimulation and control water breakthrough,research was conducted on hydraulic fracturing patterns and fracture parameters of horizontal well staged fracturing according to the characteristics of five-spot injection-production well pattern for a tight sandstone oil reservoir in the Ordos Basin.Hydroelectric simulation was conducted on fracturing methods for the pattern,and then the optimal fracturing method and fracture pattern were selected.The specific parameters of staged hydraulic fracturing were optimized using reservoir numerical simulation methods.Hydroelectric simulation showed that staged fracturing would increase the low-pressure area by 36.4 % and would increase productivity by 72.5 % in comparison with traditional dual-wing fracturing,and the spindle-shaped fracture pattern was most suitable for five-spot injection-production pattern.The best values were obtained when the angle between reservoir boundary and the fracture toes trend,fracture spacing and fracture conductivity were 23.2°,92.7 m and 15 D·cm respectively.Study results were used as reference for the fracturing design of Well YP-8 which had achieved goods results,with daily fluid production of 22.66 m3 and oil production of 18.11 t,with stable production until the time of the writing of the results.The results showed that spindle-shaped fracture pattern would achieve better near-wellbore region seepage conditions,would result in higher production and would prevent water channeling.