摘要
汶川地震序列中为数很少的深度大于30km的余震是否存在,对解释汶川地震的成因机制具有重要意义。本文分析了汶川地震序列中26个"恰好"发生在观测台站下方的小地震——"台下地震",利用这种地震与台站之间的特殊组合来确定这些地震的震源深度,以期为地震精确定位提供"GT事件"。在这26个地震中,有两例的震源深度约36km,尽管仍与所采用的地壳结构模型有关,却也提供了深度大于30km的余震存在的直接证据。
Whether there exist events with depths larger than 30km in the aftershock sequence is a critical problem in the seismogenetie model of the 2008 Wenehuan earthquake. In this work, we considered 26 aftershocks ＂just underneath＂ seismic stations. Making use of such special station-event configuration to determine the depths of these micro-earthquakes provided accurate relocation of aftershocks with a reference set of ＂ground truth （GT） events＂. In these aftershocks, two events have the depth about 36km. Although still being structure-model-dependent, this observation provides a direct evidence for the existence of the events deeper than 30km.
出处
《中国地震》
CSCD
北大核心
2009年第2期113-122,共10页
Earthquake Research in China
基金
国家科技部项目(2004CB418406)资助
关键词
地震定位
汶川地震
余震序列
GT事件
Location of earthquakes Wenchuan earthquake Aftershock sequence Groundtruth events
