利用远震接收函数反演黔江地震台下方的速度结构

Velocity Structure Inversion beneath Stations of Qianjiang Seismic Network Using Teleseismic Receiver Function

本文选取黔江地震台2007年至2011年记录到的60个远震宽频带数字地震记录，采用频率域反褶积法获得台站的接收函数，并用H．Kappa叠加法来反演台站下方的地壳厚度和泊松比，最终得到了黔江地震台下方的地壳速度结构。同时，通过H．Kappa法反演得到的台站下方的地壳厚度作为波速反演的约束条件，以减少反演的非唯一性。计算结果显示，黔江地震台下方的地壳厚度为44kin，这与广泛认同的中国大陆中西部地区莫霍深度在38--45km基本一致。本文对增强该地区深部地质构造特征研究和孕震机制分析具有积极的意义。

On basis of 60 tele-seismic broadband digital seismic records from 2007 to 2011 recorded by Qianjiang seismic station, frequency deconvolution method is used to calculate receiver functions and H-kappa stacking method is adopted to inverse the thickness and Poisson ratio in crust of this area. Then the crustal thickness inversed by H-Kappa stacking method is used as a constraint for velocity inversion beneath the seismic station in order to reduce inversion non-uniqueness. The result shows that the crustal thickness beneath Qianjiang seismic station is about 44 km. This is consistent with the Moho depth （between 38 and 45 kin） in the central and western regions in China. Our results are significant in understanding of local deep structure and in seismo-genetic analysis.