1988年10—12月的全球地震动态

DEVELOPMENTS IN WORLD SEISMICITY FOR OCTOBER--DECEMBER, 1988

中缅边界地震和苏土边界地震接连发生,亚欧带地震活动急速发展,并开始出现向西迁移的趋势。1987—1988年两年内全球未发生 Ms≥7.7级大地震。估计1993年以前亚欧带有可能发生一次 a 级大地震。

During the second quarter of the year 1989,the global seismicity increased,and a great earthquake of magnitude 8.3 occurred in Macquarie Island.There were also some seis- mic activities on the eastern part of the Eurasian belt and strong earthquakes also occurred in the east of Baikal Lake region.Results of statistics of data from PDE of USA indicated that the level of global seismicity of the year 1988 was lower;the frequency ratio of deep to shallow earthquakes was higher;the seismic activities on the American seismic belt dec- reased and at the same time that on the Eurasian seismic belt increased.