Abstract:
August 3,2014 before the Ludian 6.5 earthquake,multiple deformation measurement items witnessed short “abnormal” changes from the epicenter of less than 50 km Zhaotong seismic station,and accompanied by continuous rainfall during the event.How to remove the effects of rainfall,it is important to extract effective information before the earthquake.In this paper,using Zhaotong station tilt,strain observation data and auxiliary meteorological observation data,by taking into account the time lag of the mathematical regression model method,we quantitatively analyze the impact of rainfall on Zhaotong Station.The results show that the correlation between the measured items and the rainfall is evident and the anomaly of short pre-earthquake is near the regression line,which could be affected by rainfall.In addition,on the basis of collecting the changes of observation environment (urban construction,etc.) around Zhaotong station,the process of influencing Zhaotong station has been explored