We explore the physical phenomenon of acoustic waves induced at the interface between two different anisotropic rock media.Specifically,one medium is a transversely isotropic medium with a vertical axis of symmetry(VT...We explore the physical phenomenon of acoustic waves induced at the interface between two different anisotropic rock media.Specifically,one medium is a transversely isotropic medium with a vertical axis of symmetry(VTI medium)and the other one is a transversely isotropic medium with a tilt axis of symmetry(TTI medium).By solving the Kelvin-Christoffel equation,an eighth-order polynomial is established for reflection and refraction angles,which is confirmed from SnelFs law.Three types of analytical expressions of the polarization coefficients of the induced waves are obtained corresponding to different incident angle regions.An effective algorithm has been developed for numerical analysis of the polarization coefficients.Applying characteristic anisotropic parameters reported in the literature,the influencing factors on reflection and refraction coefficients are analyzed,e.g.,the anisotropy,the tilt-angle of rock-layer,and the incident-angle.The calculated reflection and refraction coefficients have been rechecked for energy conservation.展开更多
在论文“各向异性介质界面模式转换波Ⅰ:理论分析”给出的VTI-TTI(Transverse Isotropy with a Vertical Axis of Symmetry-Transverse Isotropy with a Tilted Axis of Symmetry)介质界面上产生的模式转换波极化系数的解析表达式和该...在论文“各向异性介质界面模式转换波Ⅰ:理论分析”给出的VTI-TTI(Transverse Isotropy with a Vertical Axis of Symmetry-Transverse Isotropy with a Tilted Axis of Symmetry)介质界面上产生的模式转换波极化系数的解析表达式和该界面反射/折射系数的计算表达式的基础上,选择各向异性页岩-泰勒砂岩界面和各向异性页岩-油质页岩界面作为界面系统,利用MATLAB进行仿真,对各向异性介质界面反射和折射特性、产生的模式转换波的极化状态以及出现的一些物理现象进行了分析和解释。使用改进后的Daley-Hron各向异性介质界面模型,分析了地层各向异性和折射TTI介质倾斜角对界面第一临界角的影响。应用能量守恒定律和声学边界条件验证了推导出的在各向异性地层界面产生的模式转换波极化系数和该界面反射/折射系数的正确性。发现某些各向异性地层界面似乎存在一个对应折射SV(Shear Vertical)波的入射临界角(第二临界角),但是在实际中并不存在的物理现象。展开更多
基金the Na-tional Natural Science Foundation of China(Grant No.41974130)the Physical Sciences Division at The University of Chicago.
文摘We explore the physical phenomenon of acoustic waves induced at the interface between two different anisotropic rock media.Specifically,one medium is a transversely isotropic medium with a vertical axis of symmetry(VTI medium)and the other one is a transversely isotropic medium with a tilt axis of symmetry(TTI medium).By solving the Kelvin-Christoffel equation,an eighth-order polynomial is established for reflection and refraction angles,which is confirmed from SnelFs law.Three types of analytical expressions of the polarization coefficients of the induced waves are obtained corresponding to different incident angle regions.An effective algorithm has been developed for numerical analysis of the polarization coefficients.Applying characteristic anisotropic parameters reported in the literature,the influencing factors on reflection and refraction coefficients are analyzed,e.g.,the anisotropy,the tilt-angle of rock-layer,and the incident-angle.The calculated reflection and refraction coefficients have been rechecked for energy conservation.
文摘在论文“各向异性介质界面模式转换波Ⅰ:理论分析”给出的VTI-TTI(Transverse Isotropy with a Vertical Axis of Symmetry-Transverse Isotropy with a Tilted Axis of Symmetry)介质界面上产生的模式转换波极化系数的解析表达式和该界面反射/折射系数的计算表达式的基础上,选择各向异性页岩-泰勒砂岩界面和各向异性页岩-油质页岩界面作为界面系统,利用MATLAB进行仿真,对各向异性介质界面反射和折射特性、产生的模式转换波的极化状态以及出现的一些物理现象进行了分析和解释。使用改进后的Daley-Hron各向异性介质界面模型,分析了地层各向异性和折射TTI介质倾斜角对界面第一临界角的影响。应用能量守恒定律和声学边界条件验证了推导出的在各向异性地层界面产生的模式转换波极化系数和该界面反射/折射系数的正确性。发现某些各向异性地层界面似乎存在一个对应折射SV(Shear Vertical)波的入射临界角(第二临界角),但是在实际中并不存在的物理现象。
