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用喜马拉雅西北部喜马偕尔地区强震台网数据的S波傅里叶振幅谱估计了场地放大和S波衰减(Qβ)。分析中使用了在震源距离R=9～48km范围13个台站记录的从M3.4到5.4震级范围的8个地震的60个三分向记录。使用时间序列的S波震相的水平与垂直(H/V)傅里叶谱比分析了场地放大的特征。除了2～4Hz的窄频率范围外,平均放大系数接近于1。H/V比的总体特征与研究区的局部地质条件一致。对0.2≤f≤20Hz,S波品质因子Q(f)估计为103f0.66,其有效性得到了从新Q(f)值导出的计算路径衰减函数的检验。估算的Q(f)值也与以前对喜马拉雅地区Q值的研究结果进行了比较。
The field amplification and S wave attenuation (Qβ) were estimated using the S-wave Fourier amplitude spectrum of the strong seismographic network in the Himalayas region, northwestern Himalayas. In the analysis, 60 tristropic records of 8 earthquakes in the magnitude range from M3.4 to 5.4 recorded at 13 stations with a source distance R = 9-48 km were used. The characteristics of field amplification were analyzed using horizontal and vertical (H / V) Fourier spectral ratios of the S-wave phase of the time series. With the exception of the narrow frequency range of 2 to 4 Hz, the average amplification factor is close to unity. The overall characteristics of H / V ratio are consistent with the local geological conditions in the study area. For 0.2≤f≤20Hz, the S-wave quality factor Q (f) is estimated as 103f0.66, whose validity is verified by the calculated path attenuation function derived from the new Q (f) value. The estimated Q (f) values are also compared with previous studies of Q values in the Himalayas.