Distributed sensing of microseisms and teleseisms with submarine dark fibers
Distributed sensing of microseisms and teleseisms with submarine dark fibers
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DOI：
10.1038/s41467-019-13262-7
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发表时间：
2019-12-18
影响因子：
16.6
通讯作者：
Martins, Hugo F.
中科院分区：
文献类型：
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作者：
Williams, Ethan F.;Fernandez-Ruiz, Maria R.;Martins, Hugo F.
海洋中稀疏的地震仪器限制了我们对地球深部动力学和海底地震的理解。分布式声传感（DAS）是一种将光纤转换为地震传感器的新兴技术，它使我们能够利用现有的海底电信电缆进行地震监测。在这里，我们报告了在比利时近海沿4192传感器海底DAS阵列观测到的微地震、局部地表重力波和远震地震。我们在现场观察了相反的海洋表面重力波群是如何产生双频地震肖尔特波的，这是朗格-希金斯微震产生理论所描述的。我们还从2018-08-19 M(w)8.2斐济深地震中提取了0.01-1 Hz频段的P波和s波相位，尽管高频波形保真度较低。这些结果表明DAS在下一代海底地震台网中的巨大潜力。
Sparse seismic instrumentation in the oceans limits our understanding of deep Earth dynamics and submarine earthquakes. Distributed acoustic sensing (DAS), an emerging technology that converts optical fiber to seismic sensors, allows us to leverage pre-existing submarine telecommunication cables for seismic monitoring. Here we report observations of microseism, local surface gravity waves, and a teleseismic earthquake along a 4192-sensor ocean-bottom DAS array offshore Belgium. We observe in-situ how opposing groups of ocean surface gravity waves generate double-frequency seismic Scholte waves, as described by the Longuet-Higgins theory of microseism generation. We also extract P- and S-wave phases from the 2018-08-19 M(w)8.2 Fiji deep earthquake in the 0.01-1 Hz frequency band, though waveform fidelity is low at high frequencies. These results suggest significant potential of DAS in next-generation submarine seismic networks.