基于避免断层激活机制的组合压裂模式研究
Combined Fracturing Mode Based on Avoiding Fault Activation Mechanism
付海峰 1刘鹏林 2陈祝兴 1翁定为 1马泽元 1李军3
作者信息
- 1. 中国石油勘探开发研究院
- 2. 中国石油大学(北京) 石油工程学院
- 3. 中国石油大学(北京) 石油工程学院;中国石油大学(北京) 克拉玛依校区石油学院
- 折叠
摘要
页岩气井多级压裂过程中的套管剪切变形问题日益严重,甚至出现了水力压裂诱发断层激活造成邻井套管变形的现象,这导致相邻水平井压裂不能顺利进行,严重影响了区块产能建设,而降低泵压及排量等现有方法对套管变形控制效果不明显.为此,基于Mohr-Coulomb准则建立了页岩气井井间断层激活评价模型,揭示了常规压裂模式下井间断层激活机理,提出了一种基于避免水力压裂诱发断层激活机制的组合压裂模式.研究结果表明:常规压裂模式下井间断层区域均会被激活,导致相邻水平井丢段;随井间距增加及水平井夹角减小,水平井丢段长度增加;通过采用拉链-顺序-同步组合压裂模式优化断层附近多井多段压裂顺序,可达到避免断层提前激活、缩短水平井丢段长度的效果.研究结果可为页岩气水平井断层激活及套管变形控制提供理论指导.
Abstract
The problem of casing shear deformation in the multistage fracturing process of shale gas wells is becoming increasingly serious,and more seriously,a phenomenon of hydraulic fracturing induced fault activation which causes casing deformation in adjacent wells occurs,which leads to the inability of fracturing in adjacent hori-zontal wells to proceed smoothly,seriously affecting the productivity operation of blocks.However,the existing methods such as reducing pump pressure and displacement have not shown significant control effects on casing de-formation.Based on the Mohr-Coulomb criterion,an interwell fault activation evaluation model for shale gas wells was built,revealing the interwell fault activation mechanism under conventional fracturing modes,and proposing a combined fracturing mode based on avoiding hydraulic fracturing induced fault activation mechanism.The results show that under conventional fracturing mode,the fault areas between wells would all be activated,leading to the loss of section in adjacent horizontal wells.As the well spacing increases and the included angle of horizontal well decreases,the lost section length of horizontal well increases.By means of adopting the zipper-sequential-synchro-nous combined fracturing mode to optimize the multi-well multistage fracturing sequence in the vicinity of fault,the effect of avoiding early activation of faults and reducing the lost section length of horizontal well can be achieved.The research results provide theoretical guidance for fault activation and casing deformation control in shale gas hor-izontal wells.
关键词
页岩气水平井/多级压裂/断层激活/压裂模式/套管变形Key words
shale gas horizontal well/multistage fracturing/fault activation/fracturing mode/casing de-formation引用本文复制引用
基金项目
国家自然科学基金联合基金重点支持项目(U22A20164)
中国石油大学(北京)克拉玛依校区引进人才基金项目(XQZX20220019)
克拉玛依市科技计划项目创新环境建设计划(创新人才)(20212022hjcxrc9)
出版年
2024
NETL
NSTL
维普
万方数据