小震频度异常新方法初探

摘要

The increasing small earthquake activities exist before the medium-strong earthquakes,but it is a common phenomenon that the small earthquake activities increased and decreased periodically.So it is difficult to predict the medium-strong earthquakes only by the phenomenon.This paper has studied Balinzuoqi MS5.9 earthquake and Dongwuzhu MS5.9 in inner Mongolia in 2003 based on a new method studying if the small earthquake frequency changed by the changing spatial pattern.The results showed that we can get obvious anomaly frequency of small earthquake and the medium and short term anomaly index before medium-strong earthquake by the new method.%尽管小震增强现象在多数中强地震前存在,但是这种周期性的小震活动强弱交替轮回过程是普遍存在的。因此,利用小震活动的增强对未来中强地震的预测比较困难。本文尝试根据小震活动空间格局是否改变来统计小震频度,并通过此方法研究了2003年内蒙巴林左旗MS5.9级地震和2004年内蒙东乌珠MS5.9级地震。结果表明：利用新方法统计小震的频度更能突出中强地震前的小震频度异常,能够有效的提取中强地震前的中短期异常指标。