地震活动性的综合判断

地震活动性的许多特点在中强震之前会有所显示,本文试图选用其中某些指标,采纳ISODATA模糊聚类方法进行多项地震活动性指标的综合判断.该方法将样本反复聚类,直到达到一定精度要求为止,且不易出现预报样本独立成类问题.当所选的每项指标均携有一定有震模糊信息(平均有震从属度大于0.5)时,该方法可以综合多项指标作合理判断,把有震、无震样本归入不同类别.由待预报样本所进入类别的震情性质得到预报信息. 本文作了月预报和半年预报的实例验算,结果良好. 

THE COMPREHENSIVE JUDGEMENT FOR SEISMIC ACTIVITY

As is well known, before most strong earthquakes some properties of seismicity appear. Taking several statistical indexes of seismicity, the ISODATA fuzzy clustering analysis is used to do comprehencive judgement of earthquake hazard. This method has two advantages. One is a certain accuracy can be fulfil, the other is it is probably impossible to classify the predicted sample of the forthcoming period into an independent class. If each selected index carries some fuzzy information, a reasonable judgement for earthquake hazard could be made according to whether the predicted sample falls into a class having seismic risk or a class without seismic risk.Two actual examples, one a -month and the other a-half-year-prediction, are calculated.