Welcome to EARTHQUAKE,

EARTHQUAKE ›› 2020, Vol. 40 ›› Issue (2): 1-17.doi: 10.12196/j.issn.1000-3274.2020.02.001

    Next Articles

Active State and Trend on Strong Earthquakes in North China

XUE Yan1, JIANG Xiang-hua1, LIU Gui-ping2   

  1. 1.China Earthquake Networks Center, Beijing 100045, China;
    2.Beijing Earthquake Agency, Beijing 100038, China
  • Received:2019-09-29 Online:2020-04-30 Published:2020-04-24

Abstract: Historic strong earthquakes occurred frequently in North China, while the earthquakes with MS≥6.0 has been quiet for nearly 22 years since the 1998 Zhangbei MS6.2 earthquake. Scholars are very concerned about the activity trend of strong earthquakes and there are different views. This paper discusses the rhythmic characteristics of active and quiet periods of earthquakes with MS≥6.0, applies the technique of Morlet wavelet transform to quantitatively analyze the seismicity periodicities, and compares the seismicity features and duration time of the transition section from the active to quiescent period. It is studied that the spatial distribution of earthquakes in active periods, the comparison of strain release rates in active period, quiet period and quiet episode, statistical characteristics of the quiet episode duration time, the currently remarkable seismic quiescence of MS≥5.0 earthquakes, and regional seismicity features of MS≥5.0 earthquakes before the earthquakes with MS6.0~6.9 and with MS≥7.0 in North China. It is believed that the present situation is in the transition section or has been entered the quiet period.

Key words: Strong earthquakes, Active period, Quiet period: Active episode, Quiet episode, Transition section, Strain release rate, North China

CLC Number: