摘要The tempo-spatial variation of seismic activity before great Chile MW8.8 earthquake on February 27, 2010 is studied. Some results are as follows: ① Two types of seismic gaps appeared before the Chile MW8.8 shock. One is background gap of MW≥8.0 earthquakes with 360 km length since 1900, the other is seismogenic gap formed by M≥5.5 earthquakes with 780 km length five years before the Chile earthquake; ② There was only one MW7.1 earthquake in the middle and southern part of Chile from 1986 to 2010. The obvious quiescence of MW≥7.0 earthquake is the long-term background anomaly for the Chile earthquake; ③ The quiescence of M6.5 earthquakes appeared in South American block and its vicinity during the period from 2007 to 2009, and the quietude state has been disappeared three months before the Chile MW8.8 earthquake; ④ The deep and intermediate-depth earthquake activity has been noticeablely strengthened in the subduction zone of South American block since 1993; ⑤ The great Chile earthquake shows that global seismicity is still in the active period of MW≥8.5 earthquakes since 2004. Based on the characteristics of the former two active periods, several great earthquakes with MW≥8.5 would take place in a few years. In addition, the circum-Pacific seismic belt would be the main region for MW≥8.0 earthquakes.
Abstract：The tempo-spatial variation of seismic activity before great Chile MW8.8 earthquake on February 27, 2010 is studied. Some results are as follows: ① Two types of seismic gaps appeared before the Chile MW8.8 shock. One is background gap of MW≥8.0 earthquakes with 360 km length since 1900, the other is seismogenic gap formed by M≥5.5 earthquakes with 780 km length five years before the Chile earthquake; ② There was only one MW7.1 earthquake in the middle and southern part of Chile from 1986 to 2010. The obvious quiescence of MW≥7.0 earthquake is the long-term background anomaly for the Chile earthquake; ③ The quiescence of M6.5 earthquakes appeared in South American block and its vicinity during the period from 2007 to 2009, and the quietude state has been disappeared three months before the Chile MW8.8 earthquake; ④ The deep and intermediate-depth earthquake activity has been noticeablely strengthened in the subduction zone of South American block since 1993; ⑤ The great Chile earthquake shows that global seismicity is still in the active period of MW≥8.5 earthquakes since 2004. Based on the characteristics of the former two active periods, several great earthquakes with MW≥8.5 would take place in a few years. In addition, the circum-Pacific seismic belt would be the main region for MW≥8.0 earthquakes.
Yan Xue, Jie Liu, Gang Li. Characteristics of seismic activity before Chile MW8.8 earthquake in 2010[J]. 《地震学报》英文版, 2010, 23(4): 333-341.
Yan Xue, Jie Liu, Gang Li. Characteristics of seismic activity before Chile MW8.8 earthquake in 2010. Earthquake Science, 2010, 23(4): 333-341.
