EDA介质中的弹性波

Elastic wave in EDA medium

EDA介质是地壳中广泛存在的一种方位各向异性介质，它是由定向的裂隙所引起。本文通过坐标变换推导出EDA介质弹性张量在一般坐标系下的表达式，并以Chriosteff方程和弹性波方程出发，讨论了平面波在EDA介质传播时的幔度面特征。文中利用有限差分数值计算的结果展示了弹性波在EDA介质中的传播特征，揭示了横波分裂现象及几种弹性参数的地质意义。

EDA medium is an azimuthal anisotropic medium that occurs widely and results from directional fractures in crust. The EDA medium elastic tensor in ordinary coordinate system is formulated by performing coordinate transform. The slowness surface of plane wave propagation in EDA medium is analysed by using Chriosteff equation and elastic wave equation. The paper also describes the propagation of elastic waves in EDA medium by using the numerical result of finite difference, and indicates shear wave splitting and geological meanings of several elastic parameters.