Powerful turbidity currents driven by dense basal layers.
Powerful turbidity currents driven by dense basal layers.
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DOI：
10.1038/s41467-018-06254-6
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发表时间：
2018-10-05
影响因子：
16.6
通讯作者：
Cartigny MJ
中科院分区：
文献类型：
--
作者：
Paull CK;Talling PJ;Maier KL;Parsons D;Xu J;Caress DW;Gwiazda R;Lundsten EM;Anderson K;Barry JP;Chaffey M;O'Reilly T;Rosenberger KJ;Gales JA;Kieft B;McGann M;Simmons SM;McCann M;Sumner EJ;Clare MA;Cartigny MJ
海底沉积物流（浊流）是地球上体积上最重要但记录最少的沉积物输送过程之一。直接观测的缺乏意味着基本特征仍然模棱两可，例如水流是完全稀释的还是由致密的基底层驱动。在这里，我们展示了迄今为止最详细的海洋浊流直接观测结果。蒙特利峡谷中这些强大的事件的正面速度高达 7.2 m s−1，并以 ≥4 m s−1 的速度携带重物（800 kg）。我们推断它们由快速而致密的近床层组成，这是由海底重新流动引起的，上面覆盖着超出致密层的稀云。海底重新流动可能是由于松散的峡谷底沙的扰动和液化造成的。令人惊讶的是，并非所有流量都与风暴、洪水或地震等重大扰动相关。因此，我们提供了沉积物通过海底峡谷输送到深海的新观点。主要由于缺乏观测，浊流的结构仍未得到解决。在这里，作者展示了在蒙特利湾部署了 18 个月的高分辨率监测阵列的数据，这表明浊流是由密集的近床层驱动的。
Seafloor sediment flows (turbidity currents) are among the volumetrically most important yet least documented sediment transport processes on Earth. A scarcity of direct observations means that basic characteristics, such as whether flows are entirely dilute or driven by a dense basal layer, remain equivocal. Here we present the most detailed direct observations yet from oceanic turbidity currents. These powerful events in Monterey Canyon have frontal speeds of up to 7.2 m s−1, and carry heavy (800 kg) objects at speeds of ≥4 m s−1. We infer they consist of fast and dense near-bed layers, caused by remobilization of the seafloor, overlain by dilute clouds that outrun the dense layer. Seabed remobilization probably results from disturbance and liquefaction of loose-packed canyon-floor sand. Surprisingly, not all flows correlate with major perturbations such as storms, floods or earthquakes. We therefore provide a new view of sediment transport through submarine canyons into the deep-sea. The structure of turbidity currents has remained unresolved mainly due to lack of observations. Here the authors present data from a high-resolution monitoring array deployed for 18 months over Monterey Bay, that suggests turbidity currents are driven by dense near-bed layers.
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DOI：
10.1098/rspa.1954.0186
发表时间：
1954-01-01
影响因子：
--
作者：
BAGNOLD, RA
通讯作者：
BAGNOLD, RA
影响因子：
3.9
作者：
Iverson, Richard M.
通讯作者：
Iverson, Richard M.
影响因子：
2.4
作者：
Jobe, Zane R.;Howes, Nick;Covault, Jacob A.
通讯作者：
Covault, Jacob A.
影响因子：
2.9
作者：
HEEZEN, BC;EWING, M
通讯作者：
EWING, M
影响因子：
64.8
作者：
Canals, Miquel;Puig, Pere;Fabres, Joan
通讯作者：
Fabres, Joan