用远震接收函数反演福建地区宽频带台站下方莫霍界面深度

Moho Depths beneath Broad-Band Stations in Fujian Area Inversed by Teleseismic Receiver Function

收集福建省"九五"数字地震遥测台网中8个宽频带台站的远震波形资料,应用接收函数的研究方法计算各个台站下方的接收函数,采用非线性的反演方法获得这些台站下方的S波速度结构,确定这些台站下方莫霍界面深度的分布情况。分析得到的反演结果,福建地区莫霍面的起伏不大,平均的地壳厚度约为32 km。在0～2 km之间均存在一层低速层,这与地表覆盖着一层松散的沉积层是相对应的。内陆地区台站附近莫霍界面深度较沿海地区略高,沿海台站的莫霍界面深度北部略高于南部。

Based on some teleseismic data collected from seismostations of Fujian digital network （＂Ninth Five Year Plan＂ network） , we obtained the receiver functions of these stations by the receiver function method, and inversed the crustal S-wave velocity structure under these stations by non-linear inversion method to calculate the depths of Moho. In view of the inversion results of 8 stations, the depth of Moho varies a little, and the average crustal thickness is about 32km. There exists a low velocity layer between 0-2km underground, which might be caused by the loose sediment covered on the surface. The Moho depth of inland areas is a little deeper than coastal areas, and becomes deeper from south to north in coastal areas.