摘要
研究了１９９０年４月２６日共和７．０级地震的水化学前兆场特征．结果表明：在震源区水化学趋势性异常所占的比例大，远离震源区所占的比例小，且有逐渐减小的趋势；在震源区水化学趋势性异常起始的时间早，远离震源区异常起始的时间晚，趋势异常的形态均为逐渐升高．研究认为，水化学前兆场的形成与区域应力场有关，但与震源应力场关系密切。
The features of Hydrochemical precursory field before the Gonghe M S7.0 earthquake on April 20,1990 are studied.The results show that proportion of hydrochemistry observation sites in which trend anomalies appear to all sites in focal region of the earthquake is higher than that far away from the focal region and the proportion reduces gradually as the epicentral distance increases.In the focal area the trend anomalies in which radon content in groundwater goes up gradually emerge earlier than far away from foci.The formation of hydrochemical precursory field has something to do with regional stress field,but has closer relation with focal stress field.Focal stress field may play a main role in the precursory process.
出处
《西北地震学报》
CSCD
1999年第1期1-6,共6页
Northwestern Seismological Journal
基金
中国地震局"九五"攻关项目
关键词
水化学
水氡
氡异常
前兆场
地震前兆
Hydrochemistry
Radon in groundwater
Radon anomaly
Anomalous character
Precursory field
Gonghe earthquake
