长白山火山活动状态分析

Active Level Analysis of the Tianchi Volcano in Changbaishan,China

长白山天池火山自1985年起每年6～9月开展季节性地震观测。1985～1994年平均每年记录到的火山地震在40次以内。从2002年7月开始,长白山天池火山地震数量明显增加,2003年发生1293次地震,2004年虽然地震数量略有下降,但是能量释放持续增强。近年来,长白山周边地区地震活动明显增强,2004年12月和2005年4月在距离长白山天池30多公里的抚松县发生了4.4级和4.0级构造地震。长白山附近发生了多次地震和火山震,天池口附近有强烈震感,可听到地声,并造成轻微震害。2005年8月以后火山地震渐趋平静,逐渐恢复到2002年以前的地震活动水平。本文对长白山火山地震监测的现状和监测能力进行了讨论,并从基本的观测事实出发分析研究了长白山天池火山近年来的活动水平,对其目前的活动现状态进行了初步分析。

Seismic monitoring has been conducted in the area of the Tianchi active volcano during every June to September since 1985.The volcanic seismic events were recorded about 40 times each year from 1985 to 1994.According to our observation data,it was found that the volcanic seismic events obviously increased since July,2002.The times of recorded seismic events increased to 1293 for the year 2002,the seismic events decreased in year 2004,but the released seismic energy remained increasing.This paper evaluated the ability of Changbaishan volcanic seismic monitoring,discussed the current volcano active level of Changbaishan,and presented our predictions for future active level of the Tianchi active volcano,Changbai Mountain.