地震学报Issue(5)：810-825,16.DOI:10.3969/j.issn.0253-3782.2014.05.006
大别-苏鲁及其邻近地区基于背景噪声的勒夫波群速度成像
Love wave group velocity tomography in Dabie-Sulu and its adj acent areas from seismic ambient noise
摘要
Abstract
The Dabie-Sulu orogenic belt is one of the major tectonic zones in eastern China Continent.In order to obtain the velocity structure of the crust and upper mantle,we collected the continuous horizontal components seismo-grams recorded by Shandong,Henan,Anhui,Jiangsu,Hubei seismography networks and China Broadband Digital Seismography Network during May 2009 through May 2011.Firstly,component cross-correlations (E--E,E--N,N--N, N--E)for every station pairs were performed;secondly the four component cross-correlation functions were stacked by using the phase-weight stacking method;thirdly the components (E--E,E--N,N--N,N--E)were rotated into the radial (R)and transverse (T)components to obtain empirical Green’s func-tions of Love waves;finally more than 4 000 Love wave group velocity disper-sion curves are got by frequency-time analysis (FTAN ),and the Love wave group velocity maps in the period of 6-40 s were reconstructed.The group ve-locity maps from 6 s to 10 s are well consistent with surface geological features. The results reveal high velocity anomalies in Dabie orogenic belt,Sulu orogenic belt and western Hubei uplift.North China exhibits low velocity due to its ba-sin structure;Jianghan,Nanxiang and Hefei basins also show low velocity structures.The Love wave group velocity maps at the period of 6-30 s indicate that there are high velocity anomalies in Dabie and Sulu orogenic belts,while the low velocity anomalies in the middle crust in the previous studies cannot be found in this study.On one hand,it may be due to poor depth resolution of Love waves group velocity;on the other hand,this is probably because the met-amorphic rock zone extends deeper than that in the previous studies.High ve-locity anomalies appear in Tanlu fault zone and its adj acent regions at the group velocity maps in the periods of 6-30 s,which may be caused by the upwelling of the mantle material and the mass exchange between the lower crust and upper mantle in the state of extension since the Cretaceous.关键词
背景噪声/勒夫波/群速度/互相关函数/大别-苏鲁造山带Key words
ambient noise/Love wave/group velocity/cross-correlation func-tion/Dabie-Sulu orogenic belt分类
天文与地球科学引用本文复制引用
叶庆东,丁志峰,郑晨,吕苗苗,吴萍萍,陈浩朋..大别-苏鲁及其邻近地区基于背景噪声的勒夫波群速度成像[J].地震学报,2014,(5):810-825,16.基金项目
国家自然基金（90915012）、地震行业专项（201008001）和科技部支撑项目“汶川地震断裂带科学钻探”资助． （）
