Abstract It is found that the anomalies of the double frequency (DF) microseisms in Xiangyang gravity station (XYS) before the Yingcheng MS4.9 earthquake on December 26, 2019 is continuously enhanced. By comparing the Ardhuin seismic spectra model(ASSM) and the western Pacific typhoon data, we find that the relationship between the enhancement anomalies of DF microseisms and the dominant frequency in the 10 hours before the earthquake and the western Pacific Phanfone are weaker than that of the local unknown near field homologous frequency signal. Combined with the observation and analysis of Enshi gravity station (ENS), we consider that the anomalies signal is not a slow earthquake event before the Yingcheng earthquake. 4 of the 5 earthquakes larger than MS4.0 in Badong-Zigui areas and Xiangyang-Guangji fault areas have the regularity of group activity with the earthquakes with MS4.5-5.0 near Qiyaoshan-Jinfoshan fault areas about 0.5-1 year ago. Further, their occurrence time are in the period of high noise level of DF microseisms from October to March in the next year. If the difference between the median and majority values of ENS-XYS DF microseisms baseline increases continuesly for 4 months or at a high level, it is possible to occur MS≥4.0 earthquake in the studied area. The conclusion of the anomalies before the earthquake can provide experience and reference for the occurrence period of earthquakes greater than MS4.0 near Badong-Zigui areas and Xiangfan-Guangji fault areas in the future.
WEI Jin,Lü Pinji,HAO Hongtao et al. Study on the Anomalies of the Double Frequency Microseisms before Yingcheng MS4.9 Earthquake[J]. jgg, 2022, 42(1): 88-95.
WEI Jin,Lü Pinji,HAO Hongtao et al. Study on the Anomalies of the Double Frequency Microseisms before Yingcheng MS4.9 Earthquake[J]. jgg, 2022, 42(1): 88-95.
