倾斜界面和各向异性介质对接收函数的影响  

Effects of dipping boundaries and anisotropic media on receiver functions

作　　者：房立华[1] 吴建平[1] 

机构地区：[1]中国地震局地球物理研究所

出　　处：《地球物理学进展》2009年第1期42-50,共9页Progress in Geophysics

基　　金：国家自然科学基金(40334041)资助

摘　　要：接收函数方法自Langston提出以来,经过近30年的不断发展,接收函数在提取方法、反演技术以及界面成像等方面取得了重要进展,已逐步成为研究地球内部、特别是地壳上地幔结构的重要手段.近年来,随着观测和研究的不断深入,倾斜界面和各向异性介质对接收函数的影响也逐渐引起人们的重视.本文通过建立不同的倾斜界面和各向异性模型,计算了不同模型的理论接收函数,比较系统的阐述了径向和切向分量接收函数的变化特征.通过分析发现倾斜界面和各向异性介质都能使接收函数的切向分量产生明显的能量,并使径向和切向分量呈现周期性的变化.倾斜界面和各向异性介质产生的接收函数波场特征的差异主要表现在周期性和转换震相的到时差上.通过分析不同方位角的径向和切向接收函数,研究直达P波和PS转换波振幅及到时随方位角的变化规律,可以较好地区分倾斜界面和介质各向异性的影响.Great progresses have been made in receiver function extracting methods,inversion methods and interface tomography methods since the 1970 s.The receiver function method has been widely used in studying S wave velocity of crust and upper mantle.With the in-depth observation and research,the effects of dipping boundaries and anisotropic media on receiver functions have attracted to geophysicists′ attention.We constructed dipping boundary models and different anisotropic models and examined azimuthal variations of the synthetic radial and transverse receiver functions.For dipping boundaries and anisotropic layers,they can cause obvious energies on transverse component and show periodicity variations as a function of back azimuth.The main differences manifest on periodicities and arrivals.By analyzing the variation characteristics of direct P wave and Ps conversions on radial and transverse components,we can distinguish the effects of dipping boundaries and anisotropic layers on receiver functions.

关 键 词：接收函数 倾斜界面 各向异性 地壳 

分 类 号：P315[天文地球—地震学]