杨静儒,龚斌,周永炳,樊晓东,史晓东
YANG Jingru,GONG Bin,ZHOU Yongbing,FAN Xiaodong,SHI Xiaodong

• 1:中国石油勘探开发研究院
• 2:中国地质大学(武汉)资源学院
• 3:大庆油田有限责任公司勘探开发研究院
• 4:黑龙江省致密油和泥页岩油成藏研究重点实验室

摘要(Abstract)：

页岩储层非均质性强,导致水力压裂裂缝的扩展行为复杂、常规方法模拟难度大。压裂人工缝扩展的有效模拟和预测对页岩油藏的开发至关重要。引入分形因子理论,对页岩储层压裂人工缝的复杂度进行定量描述,建立压裂缝与弹性模量、泊松比和脆性指数等储层岩石力学参数之间的关系,在微地震监测成果的基础上,应用非结构化网格的离散裂缝技术,精细模拟页岩储层压裂人工缝的复杂形态。案例井压裂模拟结果表明,考虑分形因子的模拟半缝长与微地震监测相对误差平均为7%,而不考虑分形因子的模拟结果与微地震监测相对误差平均达53%,运用该方法能对页岩储层压裂人工缝的扩展过程进行有效刻画表征。该模拟方法为压裂效果评估与多段压裂水平井的优化设计提供了有力支撑。
Due to the strong heterogeneity of the shale reservoirs, the propagation of the hydraulic fractured cracks is rather complicated, as a result, the simulation by means of the conventional method is hardly characterized. However, the effective simulation and prediction of the fracture network propagation are critically important to the development of the shale oil reservoirs. The fractal factor theory was introduced to quantitatively characterize the complexity of the fractured cracks of the shale reservoirs and establish the relationships between the cracks and Young's modulus, Poisson's ratio, brittleness index and other rock mechanics parameters. On the basis of the monitored results of the microseismic survey, with the help of the discrete fracture technique of the non-structural network, the complicated configuration of the fractured cracks in the shale reservoirs was finely characterized. The simulated results of the case well show that the average relative error of the half-fracture length between the simulated one considering the fractal factor and the microseismic monitoring is 7%, while this difference increases to 53% when neglecting he fractal factor, the method can effectively characterize the propagation process of the fractured cracks in the shale reservoirs. The simulating method has provided the strong support for the evaluation of the fractured effects and the optimized design of the multi-staged fracturing horizontal well.

关键词(KeyWords)： 分形因子;非均质;页岩储层;缝网扩展;微地震;离散裂缝
fractal factor;heterogeneity;shale reservoir;fracture networks propagation;microseismic survey;discrete fracture

Abstract:

Keywords:

基金项目(Foundation): 国家重大科技专项“松辽盆地致密油开发示范工程”(2017ZX05071)

作者(Author): 杨静儒,龚斌,周永炳,樊晓东,史晓东
YANG Jingru,GONG Bin,ZHOU Yongbing,FAN Xiaodong,SHI Xiaodong

DOI: 10.19597/j.issn.1000-3754.202004055

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