怀来2井水氡前兆异常特征分析

ANALYSIS TO THE CHARACTERS OF WATER RADON'S PRECURSORY ANOMALIES IN HUAILAI NO.2 WELL

首先介绍了 1 998年张北 6.2级地震前怀来 2井水氡的异常变化 ,又根据水氡异常与京西北地区几次中强震的对应情况 ,归纳出怀来 2井的水氡前兆异常特征 :形态为下降—上升型 ,异常对应范围 1 2 0～ 1 60 km;异常出现后 2 8～

The variation of water radon anomalies before Zhangbei Ms6.2 earthquake(1998)has been introduced.Based on the correspondence of water radon anomalies with the medium and large earthquake in the northwest region of Beijing,the character of water radon precursory anomalies in Huailai No.2 well has been summarized.The anomalies'shape character is from decreasing to increasing.The anomalies'functioning range is about 120～160km.Earthquakes usually occur within 28～55 days when the anomaly appear.