页岩油储层补能前后四维地应力模拟及加密井复杂裂缝扩展规律研究  

Four-dimensional in-situ stress simulation before and after energy replenishment in shale oil reservoirs and research on complex fracture propagation law in infill wells

作　　者：苏子龙 杨钊[2] Su Zilong;Yang Zhao(Huamei Futai Oil and Gas Production Technology Service Co.,Ltd.,Nanjing 210000,China;School of Petroleum Engineering,Northeast Petroleum University,Daqing 163318,China)

机构地区：[1]华美孚泰油气增产技术服务有限责任公司,江苏南京210000 [2]东北石油大学石油工程学院,黑龙江大庆163318

出　　处：《能源与环保》2024年第9期141-148,共8页CHINA ENERGY AND ENVIRONMENTAL PROTECTION

基　　金：中石油创新基金项目(2019D-5007-0205)。

摘　　要：针对安83井区长7含油层水平井区采出程度低、剩余油丰富的问题,结合考虑页岩油储层地质力学参数、天然裂缝等的非均质性和各向异性,建立一套地应力场与渗流场耦合机理模拟方法,将传统油藏渗流模拟与地质力学模拟相结合,并通过压裂施工参数、现场试井数据、微地震监测数据等,开展了储层补能前后四维地应力模拟及加密井复杂裂缝扩展规律研究。研究结果表明,该区储层杨氏模量高、泊松比低,易发生破裂;大规模压裂可以形成复杂裂缝,基本上为长250 m、宽80 m的多簇式裂缝条带;水介质补能能够起到均匀补能效果,效果比气介质好;老井补能至原始压力的80%时,压裂裂缝改造充分,裂缝扩展均衡,老井单井补能液量5000 m^(3)最优;300 m加密井补能至原始地层压力的120%时,压裂后改造较充分,单井补能液量25000m^(3)左右最优。该模拟分析方法对同类型油藏地应力模拟及裂缝扩展规律研究有重要指导意义。Aiming at the problems of low production degree and abundant remaining oil in the horizontal well area of Chang 7 oil-bearing layer in the An 83 well area,taking into account the heterogeneity and anisotropy of shale oil reservoir geomechanical parameters,natural fractures,etc.,a set of the coupling mechanism simulation method of in-situ stress field and seepage field was established,traditional reservoir seepage simulation with geomechanical simulation were combined,and through fracturing construction parameters,on-site well testing data,microseismic monitoring data,etc.,the four-dimensional in-situ stress simulation before and after reservoir energy replenishment and study of the propagation law of complex fractures in infill wells were conducted.The results show that the reservoirs in this area are high in Young′s modulus and low in Poisson′s ratio,and are prone to fracture;large-scale fracturing can form complex fractures,which are basically multi cluster fracture bands with a length of about 250 m and a width of about 80 m;water medium energy replenishment can play a uniform energy replenishment effect,and the effect is better than gas medium;when the old well is replenished to 80%of the original pressure,the fracturing fractures are fully reformed and the fractures expand evenly,5000 m^(3)of energy replenishment fluid is optimal for a single well in old wells;when the 300 m infill well replenishes energy to 120%of the original formation pressure,the fracturing after fracturing is sufficient,and the optimal amount of energy replenishment fluid for a single well is about 25000 m^(3).The simulation analysis method has important guiding significance for the simulation of the in-situ stress of the same type of reservoir and the study of the fracture propagation law.

关 键 词：页岩油 储层补能 四维地应力模拟 裂缝扩展规律 地应力场与渗流场耦合 

分 类 号：TE34[石油与天然气工程—油气田开发工程]