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本文利用了北京大学在山西地堑的34个台站以及中国地震局台网中心在鄂尔多斯地区46个台站的远震波形数据,运用双平面波干涉的面波层析成像方法,提取瑞利面波相速度频散曲线,开展台阵覆盖区三维速度结构反演,据此分析了研究区地壳和上地幔的结构特征。结果表明,瑞利面波相速度分区特征显著,山西断陷盆地和渭河断陷盆地的相速度整体偏低。鄂尔多斯块体在莫霍面以下有明显高速异常,表明该地块为构造稳定的克拉通块体,鄂尔多斯块体的岩石圈下界面在120～140km的深度左右。与此相反,山西断陷盆地和渭河断陷盆地地下70～120km左右均有低速异常,显示这两个地区构造活动活跃,这也与该区域历史上多次发生强震是相符的。
In this paper, 34 stations of Peking University in Shanxi Graben and teleseismic waveform data of 46 stations in Ordos area of China Earthquake Administration Network Station are used. Surface wave tomography of double-plane wave interference is used to extract Rayleigh surface Wave velocity dispersion curves are used to carry out 3D velocity structure inversion of the coverage area of the platform. Based on this, the structural characteristics of the crust and upper mantle in the study area are analyzed. The results show that the Rayleigh wave facies velocity subdivision is significant, and the phase velocities of the Shanxi fault basin and the Weihe rift basin are generally low. Ordos blocks have obvious high-speed anomalies below the Moho, indicating that the block is a stable craton block, and the lithospheric interface of the Ordos block is about 120 ~ 140 km deep. In contrast, the low-velocity anomalies in the subsurface of both the Shanxi fault basin and the Weihe rift basin range from 70 to 120 km, indicating tectonic activity in these two regions, which is also consistent with the frequent occurrence of strong earthquakes in the history of the region.