【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。更多还原

【Abstract】 In this paper,we use ambient noise tomography to study the Shanxi regional crustal velocity structure and deep tectonics.The data includes 7months(2014January to 2014July)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.更多还原