【摘要】 首先对ISC、SCSN与CRN地震目录进行地方时转换 ,并进行序列统计 ,建立了地方时地震时间频度分布 ,然后对地震地方时序列做了频谱分析 ,以提取地震序列中的特征周期成分 .地方时统计结果显示 :( 1 )地震频度在地方时 9时和 1 9时附近最低 ,0时和 1 3时附近最高 ;( 2 )存在以 1 2h和 2 4h为主的周期 ;( 3)较大地震和小地震有不同的活动规律 .频谱分析的结果表明 ,ISC、SCSN与CRN地震地方时序列除了存在 1 2h、2 4h等特征周期对应日潮和半日潮之外 ,还存在 1 1 7a、1a与 1 7 5a等的周期 ,分别对应太阳黑子的活动周期、地球公转及接近对应月球升交点的回归年 .更多还原

【Abstract】 The ISC, SCSN and CRN seismic catalogue data are first transformed to the local time system and the sequence statistics are made, the time-occurring number of earthquakes are set up on the system of local time, and then the frequency spectrum analysis on the earthquake sequence is done to pick up information related to the characteristic period. The results indicate: (1) time-occurring number of earthquake is up to the maximum value at local time 0:00 AM and 1:00 PM while down to the minimum at local time 9:00 AM and 7:00 PM; (2) there are two typical periods of 12h and 24h; (3) The small earthquakes and large earthquakes are different in spatial and temporal distributions. The results of frequency spectrum analyses show that there are not only periods of 12h and 24h connected with the diurnal tide and the semidiurnal tide, respectively, but also the periods of 11.7a, 1a, and 17.5a connected with 11-year sunspot cycle, earth revolution, and nearly to ascending node tropical year of the moon, respectively.更多还原