页岩储层压后油水排采动态解释模型及矿场应用  

Interpretation model and field application of dynamic oil-water flow⁃back and production of shale reservoirs after fracturing

作　　者：贾品 潘泉羽[1,2] 于书新 李斌会 程晓刚[3] 程林松 牛烺昱 JIA Pin;PAN Quanyu;YU Shuxin;LI Binhui;CHENG Xiaogang;CHENG Linsong;NIU Langyu(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing City,102249,China;College of Petroleum Engineering,China University of Petroleum(Beijing),Beijing City,102249,China;Testing Branch of PetroChina Daqing Oilfield Co.,Ltd.,Daqing City,Heilongjiang Province,163412,China;Exploration and Development Research Institute of PetroChina Daqing Oilfield Co.,Ltd.,Daqing City,Heilongjiang Province,163712,China)

机构地区：[1]油气资源与探测国家重点实验室中国石油大学(北京),北京102249 [2]中国石油大学(北京)石油工程学院,北京102249 [3]中国石油大庆油田有限责任公司试油试采分公司,黑龙江大庆163412 [4]中国石油大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712

出　　处：《油气地质与采收率》2024年第6期127-139,共13页Petroleum Geology and Recovery Efficiency

基　　金：国家自然科学基金项目“致密储层‘压裂成藏’油水赋存状态变化机理及渗流数学模型研究”(52004307)。

摘　　要：页岩油藏大规模体积压裂后,返排与早期生产通常表现出显著的油水同产特征,定量分析油水排采动态成为解释压裂缝及储层参数的一种新手段,但目前油水排采动态解释模型及应用还较欠缺。基于页岩储层压裂后压裂液赋存假设,首先建立考虑压裂缝存在条件下的水相和油相流动方程,然后通过拟时间和拟压力变量将方程线性化,推导水相和油相动态解释模型的解析解和特征解,最终形成油相图版拟合和水相直线分析联合的排采动态解释方法。研究结果表明:在双对数诊断曲线中,油相流动表现为斜率为1/2的改造区线性流和斜率为1的改造区边界控制流,水相流动表现为斜率为1/2的压裂缝线性流和斜率为1的压裂缝边界控制流。所建立的油水排采动态解释模型可较好地解释压裂缝及储层参数。基于中国西部某页岩区块的油藏、压裂及动态资料,反演了矿场压裂井的压裂缝半长、导流能力与改造区渗透率、宽度,其中压裂缝半长为50~130 m,导流能力为20~80 mD·m;改造区渗透率为0.01~0.05 mD,宽度为24~27 m。依据反演的压裂缝及改造区参数,建立压裂水平井排采数值模拟模型,基于解释结果的模拟产量与实际值吻合程度高,且后期产量预测值合理。所建立的油水排采动态解释模型完善了页岩油藏动态分析方法,对页岩油藏排采特征定量分析、压裂效果评价及高效开发对策制定提供了依据。Flowback and early production of shale reservoirs usually show obvious characteristics of oil-water co-production after large-scale volume fracturing.Quantitative analysis of dynamic oil-water flowback and production has become a new method to explain fracture and reservoir parameters.However,the interpretation model and application of dynamic oil-water phase flowback and production are still insufficient at present.Based on the hypothesis of fracturing fluid occurrence after fracturing in shale reservoirs,this paper first established the flow equations of the water phase and oil phase considering fractures and then deduced the analytical solution and characteristic solution of the dynamic oil phase and water phase interpretation models by introducing pseudo-time and pseudo-pressure to linearize the equations.Finally,the paper developed a dynamic flowback and production interpretation method combining oil phase chart fitting and water phase linear analysis.The results show that in the log-log diagnostic curve,the oil phase flow exhibits linear flow in the stimulated zone with a slope of 1/2 and controlled flow at the stimulated zone boundary with a slope of 1,while the water phase flow exhibits linear flow in the fracture with a slope of 1/2 and controlled flow at the fracture boundary with a slope of 1.The established interpretation model of dynamic oil-water flowback and production can well explain the fracture and reservoir parameters.The half-length of fracture of the fracturing well,fracture conductivity,width and permeability of stimulated zones are well inversed based on the reservoir,fracturing,and dynamic data of a shale block in western China.Among them,the half-length of the fracture is in the range of 50-130 m;the fracture conductivity is in the range of 20-80 mD·m;the permeability of the stimulated zones is in the range of 0.01-0.05 mD;the width of the stimulated zones is in the range of 24-27 m.According to the inversion of fracture and stimulated zone parameters,the numerical simulation model of f

关 键 词：页岩储层 排采动态 解释模型 参数反演 油水两相 

分 类 号：TE357[石油与天然气工程—油气田开发工程]