Abstract:By comparing minute value of the geoelectric fields Ex and Ey at different times at Siping and Yushu stations with the geomagnetic and strain components of Changchun station, this article analyzes the relations of all physical quantities by further calculating their dominant period with FFT. The results demonstrate that: firstly, daily variation of the geoelectric fields at the two stations present double peaks and one valley, and the dominant period of NS and EW trending is 12 h, 8 h. Compared with geomagnetic field, By and Ex have high suitability of fit and Bx and Ey have suitability of fit. The dominant period 12 h is the common period. Secondly, the geoelectric storm recorded has obvious synchronous change. Thirdly, daily variation amplitude between Ey and Bx has a relative synchronous change, as does that between Ex and By. Moreover, it varies obviously with the season. Finally, some short-impending anomalies may be clearly recorded at two stations, but the form and occurrence time of anomaly before earthquakes differ: the nearer the epicentral distance, the earlier occurrence time and the bigger amplitude of anomaly.
MA Mingzhi,LI Fei,LI Xuemei. Analysis of Geoelectric Field at Siping and Yushu Station, Geomagnetic Field and Strain Component at Changchun Station of Jilin Province[J]. jgg, 2016, 36(11): 1014-1019.