摘要
为了探索汶川余震发生的时空规律,采用时空点格局的分析方法,分别对汶川MS≥4.0,MS≥4.5和MS≥5.0的余震数据进行了分析,发现在一定距离尺度和一定时间尺度上余震数据存在时空聚集.在前两组余震序列中这种时空互动在余震相距60km、260小时的范围内明显增强,而后一组余震序列中这种时空互动在余震相距80km、150小时的范围内明显增强.若不考虑余震发生的时间因素,采用完全空间随机化分析方法,得到余震在相距60km范围内聚集性明显增强.上述结果为研究汶川地震发生规律和强余震预测提供了参考.
For exploring the aftershock occurrence process of the 2008 Wenchuan earthquake, an analysis on characteristics of spatio-temporal distribution of the aftershocks is made. We successively analyzed the three aftershock series： the aftershocks with magnitude Ms≥ 4.0, the aftershocks with Ms≥ 4.5 and the aftershoeks with Ms≥ 5.0. A result is obtained that the aftershocks exhibit space-time clustering on a certain distance scale and time scale. In particular, for the first two aftershock series the space-time interaction between aftershocks obviously strengthens when the distance scale is less than 60 km and time scale less than 260 hours, while for the last series, the interaction becomes intense when the distance scale is less than 80 km and time scale less than 150 hours. A complete spatial randomness analysis on the aftershoeks regardless of their occurrence time shows that the spatial clustering of the aftershocks gradually strengthens on the condition that the distance scale is less than 60 km. The result of this study is of significance in understanding the genesis of the 2008 Wenchuan strong earthquake and in predicting aftershocks.
出处
《地震学报》
CSCD
北大核心
2009年第5期506-515,共10页
Acta Seismologica Sinica
基金
国家"973"项目(2008CB425704)资助
关键词
汶川地震
完全空间随机化
时空点格局
K-函数
Wenchuan earthquake
complete spatial randomness
Space-time clustering
K-function
