页岩压裂缝网储层应力敏感性及对产能的影响  

Stress sensitivity of shale reservoir fracture network and its effect on productivity

作　　者：田巍[1,2] 邓瑞健[3] 朱维耀[2] 国殿斌[1] 李中超[1] 龙运前 高志飞[1] 

机构地区：[1]中国石化中原油田勘探开发研究院,河南濮阳457001 [2]北京科技大学应用力学研究所,北京100083 [3]中国石化中原油田分公司,河南濮阳457001 [4]浙江海洋大学创新应用研究院,浙江舟山316022

出　　处：《油气藏评价与开发》2017年第6期71-77,共7页Petroleum Reservoir Evaluation and Development

基　　金：国家重点基础研究发展计划(973计划)“页岩气多场耦合非线性理论研究”(2013CB228002)

摘　　要：为了研究页岩压裂缝网储层应力敏感性,实验室利用全数字伺服控制器对页岩岩心进行造缝处理,使其内部产生缝网结构,并通过改变围压的方式来研究页岩缝网岩石应力敏感性,进而进一步研究页岩缝网储层应力敏感性,并分析了其对产能的影响。研究表明,压裂缝网岩石应力敏感曲线为"L"型曲线形态,曲线以9.45 MPa为分界点分为两段:第Ⅰ阶段渗透率下降幅度较大,为拟塑性形变;第Ⅱ阶段渗透率下降幅度不如前者大,以弹性形变为主,岩石成为等压力体。采用岩石应力敏感曲线第Ⅱ阶段来评价缝网储层应力敏感性更符合实际,页岩缝网储层为强应力敏感,含有明显主裂缝的岩心其敏感程度相对较弱;缝网储层应力敏感性对气井产能的影响不大为2.38%,可见应力敏感性对压裂效果较好储层的影响相对较小,建议页岩气井生产过程中建立合理的气井生产制度。In order to study the stress sensitivity of the shale reservoir fracture network, the full digital servo controller was used to produce crack in the lab, making the rock exist fracture network inside. Meanwhile, the stress sensitivity of shale rock fracture network was studied by way of changing confining pressure. And then, stress sensitivity of shale reservoir fracture network was further studied, and the relationship between the stress sensitivity and productivity was analyzed. Result shows that the curve of the stress sensitivity of shale rock fracture network is＂L-shaped＂. The stress sensitivity curve is divided at 9.45 MPa, the permeability falling range is great of the first stage, mainly occurring pseudo plastic deformation. While that in the second stage is less than former,and elastic deformation of rock skeleton body compressed is mainly occurred. The rock is an equipressure body. It is more accordant for the real reservoir to evaluate the fracture joint reservoir by the second stage. The target reservoir is strong stress sensitive reservoir, while the reservoir contained obvious main crack is relatively weaker. The fracture network reservoir stress sensitivity has less influence on the productivity of gas wells, which only reaches 2.38 %, so it is necessary to established reasonable system of shale gas well production.

关 键 词：压裂缝网 岩石应力敏感性 储层应力敏感性 等压力体 

分 类 号：TE357[石油与天然气工程—油气田开发工程]