STUDY ON THE ANOMALY OF GROUNDWATER LEVEL IN BEIDU WELL BEFORE ZHANGBEI EARTHQUAKE

The research to the variation of groundwater level in Beidu well shows that there was a rising-descending anomaly in the water level before Zhangbei Ms6.2 earthquake.Processed with secondary function, the data is also showed an anomaly.Zhangbei earthquake happened 9 months after the appearance of the anomaly.Thus we concluded that the well has some monitoring capacity for the earthquakes in North China.