摘要
引入Zaliapin等发展的基于最邻近事件距离算法的丛集地震识别方法,首先使用不同类型的数据对方法进行检验,然后对胶东半岛和沂沭带的区域小震活动进行分析。结果表明,1996年以来沂沭带的小震活动近似满足泊松随机过程,主要是背景地震活动;而胶东半岛地区小震则存在明显的成丛活动。最后将该方法应用到1976年唐山MS7.8地震序列,通过序列发展不同时段的对比分析,结果表明,随着时间的推移,唐山地震序列中受此前发生的主震和较大余震影响作用的事件越来越少,序列的丛集性明显减弱,更多的小震或许可视为反映区域应力状态的背景地震。
The clustering seismicity identification method based on nearest-neighbor distance proposed by Zaliapin et al. is adopted in this paper. Firstly, different type＇s data are used to test its validity then, the method is applied to regional seismicity in Jiaodong pen- insula and Yishu fault belt. The results show that, small earthquake activities in Yishu fault belt from 1996 satisfy Poisson stochastic process approximatively, which can be seen as background seismicity; while activities in Jiaodong peninsula area display obvious clus tering features. Finally, the method is applied to the 1976 Tangshan Ms7.8 earthquake se- quence. Comparing different stages of the Tangshan earthquake sequence, the＇results indi- cate that, with the elapse of time, events affected by the main shock and previous large aftershocks become lesser and lesser, the clustering features of the Tangshan sequenceare gradually fading out, and more and more small shocks in the sequence maybe treated as background seismicity.
出处
《地震》
CSCD
北大核心
2014年第4期100-109,共10页
Earthquake
基金
国家科技支撑计划子专题(2012BAK19B04-01-05)
中国地震局监测预报司震情跟踪青年课题(2014020103)
山东省自然科学基金(ZR2012DQ006)共同资助
关键词
丛集地震
背景地震
ETAS模型
唐山地震序列
Earthquake cluster
Background seismicity
ETAS model
Tangshan earthquake sequence
