摘要
准确、高效的获取横观各向同性页岩地层有效应力系数对于地质力学建模、井壁稳定分析等具有重要实际作用。采用声波测试、常规三轴压缩试验对川南海相龙马溪组黑色页岩动、静态弹性刚度系数、有效应力系数等开展研究。结果表明,动、静态弹性刚度系数、杨氏模量随着围压增加均升高,且动态值高于对应的静态值,平行层理方向的杨氏模量高于垂直层理,而动、静态泊松比随着围压增加及层理变化无显著规律;对于动、静态有效应力系数,随着围压增加两者均降低,垂直层理方向的有效应力系数高于平行层理方向,且静态有效应力系数高于动态值;通过拟合分析得到动、静态有效应力系数、杨氏模量线性转换关系。获得的页岩有效应力系数各向异性特征及动、静态转换关系可为页岩钻完井地质力学建模分析等提供重要支撑。
It is practically important for geomechanical modeling and wellbore stability analysis to obtain Biot coefficient of transverse isotropic shale accurately and efficiently.The dynamic and static Biot coefficient and elastic stiffness coefficient of marine-facies Longmaxi black shale in the South Sichuan Basin are investigated by using acoustic measurement and conventional triaxial compression in this study.The main results are as follows:The dynamic and static elastic stiffness coefficients,Young's modulus both increase with confining pressure,and the dynamic value is higher than the corresponding static value.The value of Young's modulus parallel to bedding is higher than that of perpendicular to bedding.However,the dynamic and static Poisson's ratio has no significant rule with the increase of confining pressure and the change of bedding.In addition,the dynamic and static Biot coefficients decrease with confining pressure.And the Biot coefficients perpendicular to bedding are higher than those parallel to bedding.On the other hand,the static Biot coefficients are higher than the dynamic results.Finally the fitting analysis shows that there is a linear conversion relationship between dynamic and static Biot coefficients and Young's modulus,respectively.The obtained anisotropic characteristics of Biot coefficient and the dynamic to static conversion relationship play an indispensable role in the geomechanical analysis in drilling and completion of shale.
作者
贾利春
JIA Lichun(Drilling and Production Technology Research Institute,CNPC Chuanqing Drilling Engineering Company Limited,Guanghan,Sichuan,618300,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2023年第S02期4130-4139,共10页
Chinese Journal of Rock Mechanics and Engineering
基金
中国石油天然气集团有限公司科学研究与技术开发项目(2021DJ41)
关键词
岩石力学
横观各向同性页岩
有效应力系数
弹性刚度系数
波速
三轴压缩试验
rock mechanics
transverse isotropic shale
Biot coefficient
elastic stiffness coefficient
wave velocity
triaxial compression test
作者简介
贾利春(1985-),男,2014年毕业于中国石油大学(北京)油气井工程专业,现任高级工程师,主要从事油气井地质力学方面的研究工作。E-mail:jlc802@163.com
