巨厚砾岩油藏水力压裂三维诱导应力数值模拟  

Numerical simulation of three-dimensional induced stress in hydraulic fracturing of giant thick conglomerate oil reservoirs

作　　者：王斌[1,2] 张景臣[3] 董景锋[1] 刘凯新 王晓清 郑伟杰 孔辉 丁祥 WANG Bin;ZHANG Jingchen;DONG Jingfeng;LIU Kaixin;WANG Xiaoqing;ZHENG Weijie;KONG Hui;DING Xiang(College of Science,China University of Petroleum(Beijing),Beijing 102249,China;Institute of Engineering and Technology,Xinjiang Oilfield Branch,PetroChina,Karamay 834000,China;Institute of Unconventional Oil and Gas Science and Technology,China University of Petroleum(Beijing),Beijing 102249,China;Xinjiang Xinyitong Petroleum Technology Co.,Ltd.,Karamay 834099,China)

机构地区：[1]中国石油大学(北京)理学院,北京102249 [2]中国石油新疆油田分公司工程技术研究院,新疆克拉玛依834000 [3]中国石油大学(北京)非常规油气科学技术研究院,北京102249 [4]新疆新易通石油科技有限公司,新疆克拉玛依834099

出　　处：《断块油气田》2024年第5期836-842,共7页Fault-Block Oil & Gas Field

基　　金：中石油战略合作科技专项“砾岩油藏压裂有效性控制机理及压裂参数优化研究”(ZLZX2020-02-07-03)、“吉木萨尔上下‘甜点’高效动用机理与立体开发技术研究”(ZLZX2020-02-07-05);克拉玛依市重点研发计划项目“超大型真三轴水力压裂模拟实验装置研发与应用”(20212022zdyf0041);克拉玛依市“揭榜挂帅”项目“非常规油气藏CO_(2)压裂提高采收率技术研究与应用”(HX20231166)。

摘　　要：巨厚砾岩储层立体井网开发模式下,多井压裂时,先压裂井对后续邻井干扰程度较大,但是目前压裂张开导致的诱导应力分布求解方法不明确,使得裂缝扩展形态模拟准确度降低,影响井组整体压裂方案设计和压后效果。针对这一问题,文中基于线弹性理论,运用位移不连续法建立了三维复杂裂缝张开诱导应力模型,模拟了巨厚砾岩立体井网条件下水力压裂后的应力场分布,并基于实际井组优化了水平井的压裂方式。结果表明:在单条裂缝张开时,相较于初始值,最小水平主应力的最大值增加了3.3 MPa,最大水平主应力的最大值增加了1.4 MPa,水平应力差降低;裂缝张开产生的诱导应力大小与裂缝宽度正相关,诱导应力随着裂缝宽度的增加而增加。实际井组模拟结果表明:层间交替压裂储层改造体积(SRV)为1825×10^(4)m^(3),同层顺序压裂SRV为1360×10^(4)m^(3);层间交替压裂同一位置的后续裂缝在起裂扩展过程中受到的诱导应力叠加影响更大,裂缝复杂度更高,SRV也更大。Under the development model of three-dimensional well pattern in giant thick conglomerate reservoirs,the interference of the first fractured well to subsequent adjacent wells during multi-well fracturing is relatively great.However,the current solution method of induced stress distribution caused by the fracturing opening is unclear,which leads to the decrease of the accuracy of fracture propagation morphology simulation,and affects the integrated fracturing scheme designs and fracturing effects of the well group.To address this problem,based on the linear elasticity theory,a three-dimensional complex fracture opening induced stress model was established using the displacement discontinuity method.The stress field distribution after hydraulic fracturing under the condition of a three-dimensional well pattern in giant thick conglomerate was simulated,and the fracturing mode of horizontal wells was optimized based on actual well groups.The results show that when one fracture is opened,the maximum value of minimum horizontal principal stress increases by 3.3 MPa compared to the initial value,the maximum horizon-tal principal stress increases by 1.4 MPa,and the horizontal stress difference decreases.The induced stress generated by fracture opening is positively correlated with fracture width,and induced stress increases with the increase of fracture width.Simulation results of the actual well group indicates that the stimulated reservoir volume(SRV)of interlayer alternat-ing zipper fracturing is 1825×10^(4)m^(3),and the SRV of same-layer sequential fracturing is 1360×10^(4)m^(3).Subsequent fractures at the same location of the interlayer alternating zipper fracturing are more afcted by the superposition of induced stress during the initistion and propagat ion process of fracturing resuling in higher fracture complexity and lager SRV.

关 键 词：巨厚砾岩 水力压裂 诱导应力 SRV 

分 类 号：TE348[石油与天然气工程—油气田开发工程]