摘要
1989年10月18日22时57分开始,在华北大同一阳高地区发生一组中强震群。一个月内记到地震4286次,其中M_L≥1.0地震1372次,M≥5.5地震3次。据当地台网测定的震级为M5.7、6.1、5.6。震群序列总b值0.66,属一般震群。 前兆性地震活动图象有空区、条带、缺震、5°环等。综合这些信息,具有中期预测能力。 考虑到同年4月的巴塘M6.7地震与9月的小金M6.6地震,可以认为大同—阳高中强震群又一次显示了在我国华北—川滇存在着大尺度北东向构造活动。它们与环太平洋地震带具有平行性,与近一、二年环太平洋带地震活动非常活跃有关。
There occurred a group of moderately strong earthquake swarm in Datong-Yanggao region, North China beginning at 22h57min, October 18, 1989. 4286 earthquakes among which 1371 with ML≥ 1.0 3 with ML≥5.5 were recorded in the first month. According to the determination by local network, the magnitudes of the 3 strongest earthquakes are M 5.7, 6.1 and 5.6 respectively. The total b value of the swarm sequence is 0.66. It is a normal swarm.The precursory seismicity patterns include seismic gap, band, lack of earthquake, and 5° ring. All these information can be combined to make a for midrange earthquake prediction.Considering the Batang M 6.7 earthquake in April and the Xiaojin M 6.6 earthquake in September of the same year, we may suggest that the Datong-Yanggao mediam-strong swarm again displayed the activity of a large-scale NE tectonics along North China-Sichuan-Yan-nan region, parallel to the Cricum-Pacific seismic belt, and that the Datong-Yanggao swarm might be related with the relatively high seismicity in the Cricum-Pacific belt in recent one or two years.
出处
《地震》
CSCD
北大核心
1990年第4期1-10,共10页
Earthquake
