川西致密储层单井破裂压力计算方法综合研究

Comprehensive Study of Calculation Method about Fracture Pressure of a Well in Tight Reservoir in West of Sichuan Province

川西须家河组气藏属于低孔低渗致密深层气藏,地层压力高,5口井压裂施工其中3口井施工未成功。施工时,最高井底压力高达159.6MPa。破裂压力高,影响储层压裂改造。综合Eaton法、实测法和测井法等三种计算方法,对典型井破裂压力进行了预测,得到三口典型井破裂压力在147.0～163.7MPa之间。研究发现,测井资料求取破裂压力使用方便,易于推广。

Xujiahe reservoir in West Sichuan is a deep and tight gas reservoir with low porosity,low permeability and high formation pressure. Fracture operations were conducted in 5 wells and 3 of them were failed. The highest bottom hole operating pressure is 159.6MPa. High fracture pressure affects the fracture stimulation. So it is necessary to calculate fracture pressure. Fracture pressures in 3 typical wells are predicted by integration of three methods,i.e. Eaton method,measuring method and log analysis,the results show that the fracture pressures of those 3 typical wells are in between 147.0 MPa and 163.7 MPa; and log analysis is convenient and easily popularized to predict the fracture pressure.