The open ocean energy decay of three recent trans‐Pacific tsunamis
The open ocean energy decay of three recent trans‐Pacific tsunamis
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DOI：
10.1002/grl.50625
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发表时间：
2013-06
影响因子：
5.2
通讯作者：
A. Rabinovich;R. Candella;R. Thomson
中科院分区：
文献类型：
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作者：
A. Rabinovich;R. Candella;R. Thomson
2009年萨摩亚(8.1兆瓦)、2010年智利(8.8兆瓦)和2011年东北(9.0兆瓦)地震引发的破坏性海啸被太平洋上的大量灾难援助队台站记录下来。高分辨率(15 S)的DART记录给出了这些事件的平均能量衰变时间分别为17.3h、24.7h和24.6h。我们将这些差异归因于海啸的频率成分。具体地说，萨摩亚海啸是“高频”事件，周期为2-30分钟，而智利和东北海啸是“宽带”事件，周期为2-180分钟。频率成分的不同与震源参数的不同有关：萨摩亚是相对较小的深水地震，而智利和东北是广泛的浅水地震。对智利和东北海啸的频率相依分析表明，短周期波的衰减速度比长周期波快得多(衰减时间从15小时的2-6分钟波到29小时的60-180分钟波)。
The 2009 Samoa (Mw 8.1), 2010 Chile (8.8), and 2011 Tohoku (9.0) earthquakes generated destructive tsunamis recorded by a large number of DART stations in the Pacific Ocean. High‐resolution (15 s) DART records yield mean energy decay times for these events of 17.3, 24.7, and 24.6 h, respectively. We attribute these differences to the frequency content of the tsunamis. Specifically, the Samoa tsunami was a “high‐frequency” event with periods of 2–30 min whereas the Chile and Tohoku tsunamis were “broad‐band” events with periods of 2–180 min. Differences in frequency content are linked to differences in the source parameters: Samoa was a relatively small deep‐water earthquake while Chile and Tohoku were extensive shallow‐water earthquakes. Frequency‐dependent analysis of the Chile and Tohoku tsunamis indicates that shorter period waves attenuate much faster than longer‐period waves (decay times range from 15 h for 2–6 min waves to 29 h for 60–180 min waves).