2021年12月
Detection of hydroacoustic signals on a fiber-optic submarine cable
Scientific Reports
- 巻
- 11
- 号
- 1
- 記述言語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1038/s41598-021-82093-8
- 出版者・発行元
- Springer Science and Business Media LLC
<title>Abstract</title>A ship-based seismic survey was conducted close to a fiber-optic submarine cable, and 50 km-long distributed acoustic sensing (DAS) recordings with air-gun shots were obtained for the first time. We examine the acquired DAS dataset together with the co-located hydrophones to investigate the detection capability of underwater acoustic (hydroacoustic) signals. Here, we show the hydroacoustic signals identified by the DAS measurement characterizing in frequency-time space. The DAS measurement can be sensitive for hydroacoustic signals in a frequency range from <inline-formula><alternatives><tex-math>$$10^{-1}\,\text {Hz}$$</tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">
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</mml:math></alternatives></inline-formula> to a few tens of Hz which is similar to the hydrophones. The observed phases of hydroacoustic signals are coherent within a few kilometers along the submarine cable, suggesting the DAS is suitable for applying correlation analysis using hydroacoustic signals. Although our study suggests that virtual sensor’s self-noise of the present DAS measurement is relatively high compared to the conventional in-situ hydroacoustic sensors above a few Hz, the DAS identifies the ocean microseismic background noise along the entire submarine cable except for some cable sections de-coupled from the seafloor.
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</mml:math></alternatives></inline-formula> to a few tens of Hz which is similar to the hydrophones. The observed phases of hydroacoustic signals are coherent within a few kilometers along the submarine cable, suggesting the DAS is suitable for applying correlation analysis using hydroacoustic signals. Although our study suggests that virtual sensor’s self-noise of the present DAS measurement is relatively high compared to the conventional in-situ hydroacoustic sensors above a few Hz, the DAS identifies the ocean microseismic background noise along the entire submarine cable except for some cable sections de-coupled from the seafloor.
- リンク情報
- ID情報
-
- DOI : 10.1038/s41598-021-82093-8
- eISSN : 2045-2322