Spatio-Temporal Evolution of Electric Field Pre- and Post-Earthquakes Based on the CSES Satellite: MS5.1 Earthquakes in Songyuan, Jilin Province and Tangshan, Hebei Province
Abstract:To carry out statistical analysis of the spatio-temporal evolution of the electric field during the MS5.1 earthquakes in Songyuan, Jilin province and Tangshan, Hebei province, we use four frequency bands of the power spectrum density (PSD) data in the ULF/ELF frequency band recorded by the electric field detector (EFD) of the first seismo-electromagnetic satellite-CSES in China with geomagnetic active indexes Dst≥-30nT and Kp<3. The analysis shows that the perturbation amplitudes in the four frequency bands all increased to the high perturbation stage, which reached more than 2 times the standard deviation before the earthquake, and the earthquake occurred during the descent stage during the MS5.1 earthquake in Tangshan, Hebei province. Then, the perturbation amplitudes recovered, and it was obviously abnormal in the second frequency band. The perturbation amplitudes in the four frequency bands are very similar, and they all reached more than 2 times the standard deviation before the earthquake. The perturbation amplitudes in the four frequency bands are different during the MS5.1 earthquake in Songyuan, Jilin province. There, only the perturbation amplitude in the second frequency band reached more than 2 times the standard deviation. The perturbation amplitudes of the both earthquakes were obviously abnormal in the second frequency band (371-879 Hz) before both earthquakes, which is considered to be the dominant frequency band for seismic anomaly.
YANG Muping,QIAN Geng,ZHANG Xuemin et al. Spatio-Temporal Evolution of Electric Field Pre- and Post-Earthquakes Based on the CSES Satellite: MS5.1 Earthquakes in Songyuan, Jilin Province and Tangshan, Hebei Province[J]. jgg, 2022, 42(11): 1161-1165.