【摘要】 利用功率谱和Sompi港分析方法，对大震前地脉动及展前特殊波形等记录进行了比较深入的研究，结果表明；①较大地震前短周期地脉动及展前特殊波形频谱的峰值频率几，拐角频率人，相对频带宽度f，相对峰值人Sm／So，高频段的斜率绝对值问及Sompi港的卓越频率入等特征量均可能呈现出较明显的下降（少数为上升）异常变化；②各频谱特征量呈现异常的时间基本上同步，并与波速异常发展趋势基本相符；③以上异常变化可能反映震前孕震区地下微破裂的形成与发展过程；④地脉动特征量可能为地震中长期及短临预报的研究提供一些有用的信息，有广泛的应用前景。更多还原

【Abstract】 By using the methods of the power spectral analysis and Sompi spectral analysis,the authors have studied the short-period microseism wave form and some special wave-forms before some large earthquakes,and the results show that =before larger earthquakes,the peak frequency,corner frequency,relative width of frequency domain,relative value ofpeak spectrum,the absolute slope value of high frequencies and Sompi spectral frequencymay decrease (some may increase). So,some of them may be used as an important indexfor earthquake prediction.更多还原