Electromagnetic Abnormity Observed at Sujiatun Seismic Station and Its Relation toEarthquake

摘要

The Sujiatun seismic station is a local professional seismic observation station in the city of Shenyang, Liaoning province. Electromagnetic radiations observation apparatus, of the type EMAOS-L, are used there. In this paper, four years observation data and observed earthquakes with M_S≥4.0 were collected in the Sujiatun observation station. The characteristics of electromagnetic radiation abnormities and earthquakes are analyzed from such aspects as capabilities of the apparatus used, tectonic structure, origins of electromagnetic radiations and so on. By analysis, precursor abnormities observed at this observation station are remarkable. The electric and magnetic abnormities are with good synchronism and the abnormities can respond better to the earthquakes with the epicenter distance being less than 20km and taking place in the upper crust. At the same time, for earthquakes with large magnitudes, the variation of precursor abnormities shows a periodic diurnal variation.