选取上海佘山地震台阵16个子台记录的远震波形数据，采用时间域反褶积方法计算不同频率的P波接收函数，采用H-κ叠加搜索方法获取每个子台下方地壳厚度和vP/vS波速比值。研究结果显示：整个台阵下方地壳厚度和波速比值存在弱横向不均一性，其中上海佘山地区平均莫霍面深度较浅，约26.9 km；vP/vS比值较高，约1.87。采用最小二乘法联合多频率P波接收函数和瑞利频散曲线，反演上海佘山地震台阵下方地壳S波速度结构，结果显示，中地壳存在S波低速结构，与前人研究结果相一致。
In this paper, the teleseismic waveform data recorded at 16 sub-stations of the Sheshan Seismic Array in Shanghai are selected, and the time-domain deconvolution method is used to calculate the P-wave receiver functions at different frequencies, and the H-κ stacking method is used to obtain the thickness of the crust beneath each sub-station and the vP/vS ratio. The results show that there are weak lateral inhomogeneities in crustal thickness and vP/vS ratio beneath the whole array, with the average Moho surface depth in the Sheshan region of Shanghai being thin, about 26.9 km, and the vP/vS ratio being high, about 1.87. The inversion of the S-wave velocity structure of the crust beneath the Sheshan Seismic Array is performed by using the least-square method in combination with the multi-frequency P-wave receiver functions and Rayleigh dispersion curves, and the results show that there is an S-wave low-velocity structure in the middle crust, which is consistent with the results of previous studies.
2024,45(5): 20-27 收稿日期：2023-12-26
DOI：10.3969/j.issn.1003-3246.2024.05.003
基金项目：中国地震局地震科技星火计划(项目编号:XH240902A)
作者简介：贾思超(1992-),男,工程师,主要从事地球物理站网运维、地震预报工作。E-mail:jiasichaoA@163.com“
*通讯作者：”于海英(1970-),女,高级工程师,主要从事地震台网和台阵监测及数据处理研究工作。E-mail:6168658@qq.com
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