山西地区地壳S波速度结构  

The Crustal S-Wave Velocity Structure of Shanxi Region

作　　者：周铭[1] 徐朝繁[1] 耿伟[2] 魏运浩[1] 

机构地区：[1]中国地震局地球物理勘探中心,郑州市450002 [2]山西省地震局长治中心地震台,长治市046000

出　　处：《大地测量与地球动力学》2016年第10期912-917,共6页Journal of Geodesy and Geodynamics

基　　金：长治市活断层探测项目(GK-C-2Ⅱ)~~

摘　　要：利用山西及周边共44个宽频地震台2014-01-07地震噪声数据,反演瑞利波群速度和相速度频散,得到研究区域的三维剪切波速度。上地壳中,山西断陷带表现为较低的速度异常,而两侧的隆起区则显示高速异常;中下地壳主要表现为以北纬38.5°左右为界的南高北低的速度特征。大同盆地从浅部到中下地壳整体呈现为低速特征,与该地区广泛存在的火山群有关。In this paper, we use ambient noise tomography to study the Shanxi regional crustal velocity structure and deep tectonics. The data includes 7 months （2014 January to 2014 July） three-component continuous data recorded at 44 seismic stations of Shanxi province digital seismic networks and its surrounding . The S-wave velocity structure of the crust is inverted from Rayleigh wave dispersion maps. The S-wave velocity maps show clear lateral variations that correlate well with major geological structures and tectonic units in the study regions： in the upper crust, S-wave velocities of the Shanxi fault depression zone are relatively low at shallow depth, while the uplifts on sides of Shanxi fault depression zone show high velocity. In the mid-lower crust, the latitude -38.5°N divides the region into a northern part with a low velocity anomaly and a southern part with a high velocity anomaly. Datong basin shows low velocity in the crust, possibly related to the wide distribution of volcanoes.

关 键 词：山西断陷带 群速度 相速度 背景噪声 

分 类 号：P315[天文地球—地震学]