Monitoring seismic velocity change caused by the 2011 Tohoku-oki earthquake using ambient noise records
Monitoring seismic velocity change caused by the 2011 Tohoku-oki earthquake using ambient noise records
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DOI：
10.1029/2012gl051405
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发表时间：
2012-05-12
影响因子：
5.2
通讯作者：
Matsuoka, Toshifumi
中科院分区：
文献类型：
--
作者：
Minato, Shohei;Tsuji, Takeshi;Matsuoka, Toshifumi
以2011年3月11日东北大地震为中心，利用环境地震噪声自相关反演的散射波估计了日本东北南部地区6个月来的地震速度变化。地震和两次大余震发生后，研究区距离主震最近的地区估计速度下降幅度高达1.5%。速度变化显示逐渐愈合。速度变化的空间分布与GPS记录的静态应变变化和强震记录的三次地震中粒子速度峰值都有一定的相关性。因此，我们的研究结果表明，速度变化可能包含了地壳深处对同震应力释放的影响，以及强地震动引起的浅层影响。引用本文：Minato， S.， T. Tsuji， S. Ohmi和T. Matsuoka(2012)，利用环境噪声记录监测2011年东北大地震引起的地震速度变化，地球物理学。卷。， 39, L09309, doi:10.1029/2012GL051405。
We estimated the changes in seismic velocity in the southern Tohoku district of Japan during the six-month period centered on the 11 March 2011 Tohoku-oki earthquake, using scattered waves retrieved by autocorrelation of ambient seismic noise. The estimated velocity decrease after the earthquake, and after two large aftershocks in the study area, was as great as 1.5% in the area nearest to the main-shock. The velocity changes displayed gradual healing. The spatial distribution of the velocity change showed a correlation with both the changes in static strain, derived from GPS records, and the peak particle velocity experienced during the three earthquakes, derived from strong-motion records. Therefore, our results show that velocity changes possibly contain information from deep in the crust bearing on coseismic stress release, in addition to shallower effects due to strong groundmotion. Citation: Minato, S., T. Tsuji, S. Ohmi, and T. Matsuoka (2012), Monitoring seismic velocity change caused by the 2011 Tohoku-oki earthquake using ambient noise records, Geophys. Res. Lett., 39, L09309, doi:10.1029/2012GL051405.