摘要
根据中国大陆及周边地区 190 0年以来M≥ 6.9级地震资料 ,着重分析地震活动的时空分布特征。结果表明 :研究区地震活动具有分区、分期特征 ,整个时段可划分为 3个活跃期 (幕 ) ,第Ⅰ、Ⅱ活跃幕持续时间分别在 39和 32年左右 ,第Ⅲ活跃幕已持续了 2 2年 ,目前尚未结束 ,还可能延续 10～ 17年左右 ;在时空域内 ,地震活动出现了分区集中和地区间的交替迁移以及平静与活跃的交替现象。每个活跃幕内 ,地震活动以多周期轮回的迁移规律 ,每个活动周期首发、首发地震后的地震和结束地震地点 ,主要出现在印度板块的东、西两触角和台湾地区 ,近期首发地震始终由台湾开始 ;首发地震后的地震基本都在印度板块东触角地区 ;结束地震 ,大多在印度板块西触角地区。 1999年 9月台湾 7 6级和 2 0 0 0年 6月缅甸 7 0级地震的发生 ,意味着新一轮地震活动周期的开始 ,未来地震有可能在中国大陆西部或印度板块东触角地区集中活动的趋势。
Based on the seismic data with M ≥6.9 in regions of China's Mainland and nearby regions since 1900, we analyzed the time-space distribution of earthquakes. The results show that regions are characterized by the seismic zone and period. The whole seismic history period since 1900 can be divided into three seismic episodes. Their intervals are 39, 32 years respectively. The third seismic episode has lasted for 22 years and will go on for 10 to 17 years. The seismic situations show fluctuating changes between quiet and activity. In each active episode, the earthquake swarm comes up cyclically and the seismic positions migrate. Both beginning and ending positions of earthquake in each seismic episode are partly located in both eastern and western feelers of India block and in Taiwan regions. However in this seismic episode, the seismic episode begins with the events in the eastern feeler of India block and ends in western feeler. The new seismic episode begins with the M 7.6 September 1999 Taiwan Earthquake and the M 7.0 June 2000 Burma Earthquake. Future earthquakes will located in the western regions of China's Mainland and eastern feeler of India block.
出处
《四川地震》
2000年第4期9-16,共8页
Earthquake Research in Sichuan
