摘要
以甘肃和山西２ 个区域的历史地震资料为基础，采用地震时序分析方法，研究了这２ 个区域地震活动状态与地震形势．结果表明：（１） 区域７ 级强震在不同层次上活跃与平静交替发生；（２） 中强震在７ 级强震活跃期内伴随７ 级强震发生，在７级强震平静期内或围绕６ 级地震活动或５ 级以上地震丛集发生；（３） 甘肃目前可能正处于７ 级强震平静期以及中强地震平静期内，今后一百年或数百年内发生７ 级强震的可能性不大。
The states of local seismic activity and seismic tendency have been studied by using time progress analytical method to the historical seismic data in Gansu and Shanxi region.The results are as follow:(1) The active and quiet periods of local strong earthquakes with M S7.0 have occurred alternatively in different time scales.(2) In the active periods of strong earthquakes with M S≥7.0,the activities of moderate strong events have accompanied the occurrence of strong earthquakes with M S≥7.0,but they have accompanied the occurrence of earthquakes with M S6.0 or have occurred as cluster of events with M S≥5.0 in the quiet periods.(3) The seismic states of Gansu may be in the quiet period of both strong earthquakes with M S7.0 and moderate strong earthquakes,and the probability of occurrence of strong earthquakes with M S≥7.0 is small within one or serveral hundred years,meanwhile,the probability of occurrence of moderate strong events is also small over ten years from now.
出处
《西北地震学报》
CSCD
1999年第3期225-233,共9页
Northwestern Seismological Journal
关键词
地震
地震活动状态
地震形势
区域地震
甘肃
Historical seismological data
Time progress method
Trend prediction
Gansu
Shanxi
State of regional seismic activity
