历史强震烈度点数量的统计特征及其对历史地震参数的影响

The statistical features of intensity points of historical strong earthquakes and their impact on historical seismic parameters

以1995年出版的《中国历史强震目录（公元前23世纪～公元1911年）》为基础,首先统计了中国历史强震烈度点数量的总体分布情况,然后对历史强震烈度点数量在时间、空间和强度上的分布进行了分析,结果表明中国历史强震的烈度点资料普遍偏少.在时间和强度上,公元1500年以前,受条件所限很多历史大震没有记载或者有些记载没能流传至今,而流传下来的历史地震也仅有少数烈度点;公元元年以前,史料记载过于简单且有缺漏,导致估定的最大震级记录不超过7级;公元1500年以后才开始出现8级以上大震记录.在空间上,中国东部地区地震记载点明显较西部地区更为翔实.本文对单烈度记载点历史强震情况进行了重点分析,并将既有仪器记录又有宏观考察的现代地震按照历史地震参数获取方法进行处理,以讨论烈度点稀缺对确定历史地震参数的影响.

Based on the Catalogue of Chinese Historical Strong Earthquakes （23rd century B.C.to 1911 A.D.） published in 1995,we first analyzed statistically the overall distribution of the numbers of intensity points of Chinese historical strong earthquakes,then in time,geographical distribution and magnitude respectively.The results show that：the number of intensity points of Chinese Historical Strong Earthquakes are generally small.In time and magnitude,before 1500 A.D.,due to the conditions,many historical earthquakes were not recorded or were not passed down,yet those handed down only have limited intensity points.Because the records were too simple and incomplete,the largest earthquake which was evaluated was less than Ms7.0 in B.C.Earthquakes with Ms ≥ 8.0 were recorded only after 1500 A.D.In geographical distribution,historical earthquakes intensity points in eastern China are obviously more plentiful than western China.We focally analyzed the earthquakes with only one intensity point,and used historical seismic parameters acquisition method on modem events with both instrument records and macro investigation records to discuss the impact of scare intensity points on earthquake parameters＇ determination.