提高大庆外围油田重复压裂井效果方法探讨

Discussion of the Methods of improving the Effectiveness of the Wells Subjected with Repeated Fracturing for the Outskirt of Daqing Oilfield

通过分析重复转向压裂机理及适应的油层特征,结合现场应用,认识到重复转向压裂效果比普通压裂要好,但实现转向需要一定的地质条件,即水平最大和最小主应力差值小于4MPa。应用波速各向异性、黏滞剩磁、差应变、地应力场有限元数值模拟等方法研究了大庆外围油田15个区块的地应力特征。指出不同地应力特征的区块采取不同的重复压裂技术,可提高压裂工艺技术的适应性,提高油井重复压裂效果。该技术对开发低渗透油蔵具有一定的借鉴和指导意义。

It is recognized that the effect of repeated diversion fracturing is better than ordinary fracturing,and however,that realizing diversion needs certain geological conditions,that is,the difference of maximum principal stress and minimum principal stress should be less than 4 MPa.The geological stress characteristics of 15 blocks of Daqing Oilfield by using the finite element numerical simulation methods of wave speed heterogeneity,viscous residual magnetism,differential stress and stress field.It is raised that adopting different fracturing technologies for the blocks with different geological stress characteristics can increase the adaptability of fracturing technology and increase the effect of repeated fracturing.The technology can be a guide and be significant to the development of low permeability reservoirs.