横向各向同性粘弹性介质中的地震波

SEISMIC WAVES IN TRANSVERSELY ISOTROPIC VISCOELASTIC MEDIA

长春地质学院

Changchun University of Earth Science

在地震波正演计算中,常假设地下介质是各向同性的理想弹性介质或声学介质,而实际介质通常是各向异性和非完全弹性的。本文将讨论在横向各向同性粘弹性介质(TIVM)中传播的地震波波动方程,地震体波的相速度、群速度、能速度、极化角和品质因子等性质。理论与计算结果都表明:各向异性粘弹性介质中的地震波特性比理想介质复杂,且有其独特的性质。

In forward computation for seismic waves, subsurface media arc usually assumed to be completely clastic or acoustic. However, the real rocks are occasionally of anisotropy and incomplete elasticity, The discussion in this paper will cover a series of parameters such sa the phase velocity, group velocity, energy velocity, polarization angle and quality factor of seismic body waves propagating in transversely isotropic viscoelastic media (TIVM) as well as the corresponding wave equation. Theoretical analysis and computational results show that the properties of seismic qavcs in TIVM are more distinctive and complicated than that in ideal media.