RESEARCH ON THE CHARACTERS OF TWO XIUYAN EARTHQUAKE SWARMS AND THEIR PREDICTABIE SIGNIFICANCE

In this paper,making a systematic analysis and researching the sequence nature and character of two earthquake swarms at the Xiuyan in 1988 1 and 1999 11 To analyse the result shows that all kinds of chararacteristic parameter and forecasting target of the sequence shows clear information to prossess forecasting significance especially,the foreshock sequence in 1999 11,low b value,low h value,and small earthquake first motion symbol and wavelike character shows high consistent and stabilization,presage high concentration and stabilization for the seismic source stress field Something more,time structure of frequency distribution and time process energy liberation for foreshock sequence shows a clear characteristic thatdense calm earthquake,strengthen lighten earthquake;and the character bear a resemblance to the time space structure and the timespace process of foreshock activity of the Haicheng earthquake In the paper,the probability to take place earthquake between the two earthquake swarms is discussed,and the evaluation of the biggest magnitude is given