南北地震带北段地震活动的有序性和层次性

本文分析了南北地震带北段有记载以来6级以上强震、全新世以来海原活断层8(1/2)级大震以及海原大震极震区5级以上中强震等不同层次地震事件的时间序列,发现它们具有自相似特征,即不同层次的地震事件表现有序性、满足简单公式N=Ac^Bt或t=a+blnN。文中用最小二乘法在信度a=0.05情况下,通过线性相关检验,给出了各层次的有关系数值。 本文结果表明,地震活动是遵循尺度对应这一基本原理。这对研究地震活动分期划段,判定不同层次的地震趋势有一定参考作用。同时地震活动在不同层次表现的自相似现象也是值得进一步研究的课题。

ON THE ORDERING AND STRATIFICATION CHARACTERISTICS OF STRONG EARTHQUAKES IN THE NORTHERN PART OF THE SOUTHNORTH SEISMIC BELT

This paper discusses the time sequence of earthquake events of different stratifications in the northern part (Wudu to Yinchuan) of the south-nouth seismic belt.The results in this paper show that earthquake events of the different stratifications have the characteristics of ordering, and they were consistent with simple formula: N = AeBt or t= a+blnN. The ordinal number of a seismic event and it's time in different stratifications with confidence level = 0.05 are linearly related. The coefficients of different stratifications were obtained by means of the least squares method. The physical meaning of the coefficient of the time series b were preliminarily discussed.The results might be useful for studying division of seismic periods, discussing the tendency of the different stratifications and recognizing the stratifying of the tectonic motion or intrinsic harmoniousness.