Research Of The Relevance Between Seismos And Ionospheric Anomaly

Based on the Ionosphere Digital Data which detected by the ionosonde(vertical detection and oblique incidence detection) before seismos, this paper mainly analyse the phenomenon of the ionospheric anomaly,talk about the relationship between earthquake and ionospheric anomaly. After elaborating the basic principle of ionospheric vertical detection and oblique detection, with the parameters be received from the ionograms, and refer to the QP layer model & equator model with two peaks, I build a gaussian distribution electron density model. Then considering the effect of ionospheric transverse inhomogeneous variation, ray paths are discussed by using the step-changing ray tracing technique. According to the vertical detection ionograms, use POLAN to calculate the real-height profile of the ionosphere .By analysing the anomaly ionospheric data which detected before the wenchuan earthquake, we find that in the afternoon of May 9, three days before this earthquake, the F2 layer's critical frequency had a exceptional rise, at the same time ,the height of the maximum electron density lifted for about 40km.The nearest detecting station observed a most serious ionospheric anomaly. This means that during the wenchuan earthquake having a premonitor, there is a obvious ionospheroc anomaly.