Ionosphere TEC Anomalous Disturbance of Pre-seism

Using the observational data of fiducial station in the crustal movement observation network of China,the total electron content of Chinese region from March to August 2008 are calculated. Being assisted by the final TEC of CODE analysis center,adopting different scale statistical analysis method,we examined the TEC on sichuan earthquake. As a result,we found that the anomalous VTEC disturbances over the preparation zone of Wenchuan earthquake continuously took place in a preseismic week,which shift to magnetic equator and disappeared completely step by step.