利用远震接收函数研究湖北地区地壳结构  

Crustal Structure and Poisson Ratio beneath Hubei Province Derived from Teleseismic Receiver Functions

作　　者：何凯 杜瑞林[1,2] 董彦君 魏贵春[1,2] 申学林 戴苗[1,2] HE Kai;DURuilin;DONG Yanjun;WEI Guichun;SHEN Xuelin;DAI Miao(Hubei Earthquake Agency, 48 Hongshance Road, Wuhan 430071, China;Key Laboratory of Earthquake Early Warning, Institute of Seismology, CEA,40 Hongshance Road, Wuhan 430071 ,China)

机构地区：[1]湖北省地震局,武汉市洪山侧路48号430071 [2]中国地震局地震研究所(地震预警湖北省重点实验室),武汉市洪山侧路40号430071

出　　处：《大地测量与地球动力学》2018年第6期646-649,660,共5页Journal of Geodesy and Geodynamics

基　　金：中国地震局测震台网青年骨干培养专项(20170615)~~

摘　　要：利用2014~2015年湖北数字地震台网30个子台记录的远震波形资料,用频率域反褶积方法提取接收函数,由H-Kappa、CCP叠加方法反演得到各台站下方地壳厚度、泊松比及剖面AA′。结果表明:1)湖北地区地壳厚度总体趋势是西厚东薄,鄂西北、西南地区地壳厚度在45~55km左右,鄂东地区地壳厚度在30~35km左右;2)湖北地区泊松比值总体变化不大(0.23~0.27),说明这一地区岩石可能以中度组分为主;3)AA′剖面中出现"楼梯状"Moho面,结合相关文献分析,在武当山地区下方地壳的榴辉岩发生相变,使得相变后的下地壳密度改变而发生拆沉作用,因此鄂西地区地壳厚度发生陡变。In this paper, we calculate receiver functions of body waves under 30 stations in Hubei province, using data from the teleseismic earthquake （2014-2015）, obtaining thickness, poisson ratio, and CCP profile （AA＇）. The results show that.. （1） the crust thickness in western Hubei is thicker than in the east; crustal thickness in northwest and southwest Hubei is at about 45455 kin, in the east it is about 30-35 km; （2） the poisson ratio in Hubei province is about 0.23-0.27, which may be related to the moderate rock compositions; （3） the Moho surface looks like ＂stairs＂. In combination with related literature analysis, eclogite phase changes occur below the Earth＇s crust in the Wu- dang mountain area, so that the alternating density phase changes of lower crust delamination causes abrupt changes in western Hubei regional crustal thickness.

关 键 词：接收函数 H-Kappa叠加 地壳厚度 

分 类 号：P313[天文地球—固体地球物理学] P315[天文地球—地球物理学]