摘要
以各向异性页岩作为入射介质、泰勒砂岩作为折射介质,构成第一种各向异性岩石界面模型;以各向异性页岩作为入射介质,而用油页岩作为折射介质,构成第二种各向异性岩石界面模型。第一种各向异性岩石界面模型不存在异常入射角,而第二种各向异性岩石界面模型存在着一个对应折射P波的异常入射角。针对上述两种界面模型,本文推导了非均匀折射P波的椭圆极化方程,并对其极化状态进行了分析。计算结果表明:异常入射角的存在不仅会使折射P波的椭圆极化轨迹的形状和大小发生突变,而且还会导致其椭圆极化旋转方向发生突变。
In this paper,we study the polarization state of inhomogeneous refracted P-wave induced by two anisotropic rock interfaces.The first model is the interface between anisotropic shale and Taylor sandstone and the second one is the interface between anisotropic shale and oil shale.There is not any anomalous incident-angle for the first interface model,and there is an anomalous incident-angle corresponding to the refracted P-wave for the second interface model.An elliptical-polarization equation of the inhomogenous refracted P-wave is also derived.The calculated results show that the anomalous incident angle causes not only sharp variation of the shape and size of the elliptical-polarization trajectory,but also changes of the ellipticalpolarization rotation direction.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2018年第2期266-271,共6页
Oil Geophysical Prospecting
基金
国家自然科学基金项目(40974078
51709228)联合资助
关键词
VTI介质
椭圆极化
入射临界角
异常入射角
非均匀折射P波
VTI medium
elliptical-polarization
incident critical-angle
incident anomalous-angle
inhomogenously refracted P-wave
