STUDY ON THE DEFORMATION ANOMALY OF EARTHQUAKES IN FUJIAN-TAIWAN AREA BASED ON WAVELET ANALYSIS

In the different stages of seismogenic process,there may be a long,medium and short-term precursor abnormalities.In order to reveal the form of anomaly in different periods before moderate-strong earthquakes in Fujian-Taiwan area,we made wavelet analysis on the digital deformation observation data in Fujian province with the daily mean,hourly and minutely values.The result shows that: the abnormal signals with about 2 years period appeared in 2 to 3 years before a strong earthquake,the abnormal signals with about 1 month period appeared in 2 to 5 months before moderate-strong earthquakes,the abnormal signals with the period of half an hour to 1 hour appeared in several days to more than ten days before earthquakes.