Preliminary Study on Ionospheric Phenomena of the Wenchuan Earthquake Detected by the ICE Onboard the DEMETER Satellite
|School||China Seismological Bureau, Institute of Geophysics|
|Course||Solid Earth Physics|
|Keywords||DEMETER satellite VLF Signal-to-noise ratio Wenchuan earthquake Seismic ionospheric phenomena|
In recent years , scientists seismic electromagnetic phenomena continue to conduct in-depth study to find earthquake precursory phenomena not only exist in the lithosphere , through some coupling may exist in the atmosphere and ionosphere . With the developed countries have launched satellites for earthquake monitoring , earthquake ionospheric phenomena reported more and more , this phenomenon is also increasingly a cause for concern . This article DEMETER satellite records to the electric field data analysis over the Wenchuan earthquake area , and try to extract before and after the earthquake in the satellite height possible anomalies , and to explore the ionospheric effects of the earthquake . First, do the research at home and abroad in the field of Research summarized in brief earthquake ionosphere coupling mechanism , and a review of the existing seismic ionospheric effects research and earthquake cases . DEMETER satellite , and then introduced , including load and data products , and focus on its application in earthquake research . Subsequently, the use of DEMETER satellite flying through over the Chinese mainland , mounted on the satellite field detector to detect the signals sent from the vicinity five different VLF radio data , analysis epicenter over the region corresponding to the different frequency signals SNR in the changes before and after the earthquake . The analysis found that the distribution of signal-to-noise ratio over the earthquake zone in significantly reduced before the earthquake , after the earthquake, has been restored . This phenomenon may be related to the earthquake ionospheric effects . And we also try using a grid of abnormal localization of quantitative extraction . Finally, the paper work done is summarized , and data processing results obtained are compared with the results of previous studies , analysis of the use of satellite data processing method , the inadequacies of the papers and later studied in depth .