Allogenic and Autogenic Signals in the Stratigraphic Record of the Deep-Sea Bengal Fan.
Allogenic and Autogenic Signals in the Stratigraphic Record of the Deep-Sea Bengal Fan.
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DOI：
10.1038/s41598-018-25819-5
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发表时间：
2018-05-22
影响因子：
4.6
通讯作者：
Fox L
中科院分区：
文献类型：
--
作者：
Blum M;Rogers K;Gleason J;Najman Y;Cruz J;Fox L
喜马拉雅山脉的恒河-布拉马普特拉河水系和深海孟加拉扇代表了地球上最大的沉积物扩散系统。本文利用中新世至中更新世孟加拉扇浊积岩的碎屑锆石U-Pb物源资料，评价了异体强迫与自生过程对信号从喜马拉雅向深海传播的影响。我们的数据记录了喜马拉雅系统强烈的构造和气候强迫特征：经过长达2500公里的河流输送和100 - 1400公里的浊流输送，U-Pb记录忠实地代表了喜马拉雅的来源。此外，特定的U-Pb种群记录了雅鲁藏布江流域中新世与亚洲板块的整合，以及上新世至更新世喜马拉雅东部合结的快速切割和挖掘。然而，记录偏向于冰河时期，当时由于气候迫使海平面下降，河流延伸到大陆架上，并直接流入斜坡峡谷。最后，只有部分记录代表恒河或雅鲁藏布江的物源端元，大多数样品代表两个系统的混合。混合或缺乏混合可能代表了自生三角洲-平原侵蚀的指纹，这导致两条河流分别将沉积物输送到陆架边缘峡谷，或者像今天这样合并在一起。
The Himalayan-sourced Ganges-Brahmaputra river system and the deep-sea Bengal Fan represent Earth’s largest sediment-dispersal system. Here we present detrital zircon U-Pb provenance data from Miocene to middle Pleistocene Bengal Fan turbidites, and evaluate the influence of allogenic forcing vs. autogenic processes on signal propagation from the Himalaya to the deep sea. Our data record the strong tectonic and climatic forcing characteristic of the Himalayan system: after up to 2500 km of river transport, and >1400 km of transport by turbidity currents, the U-Pb record faithfully represents Himalayan sources. Moreover, specific U-Pb populations record Miocene integration of the Brahmaputra drainage with the Asian plate, as well as the rapid Plio-Pleistocene incision through, and exhumation of, the eastern Himalayan syntaxis. The record is, however, biased towards glacial periods when rivers were extended across the shelf in response to climate-forced sea-level fall, and discharged directly to slope canyons. Finally, only part of the record represents a Ganges or Brahmaputra provenance end-member, and most samples represent mixing from the two systems. Mixing or the lack thereof likely represents the fingerprint of autogenic delta-plain avulsions, which result in the two rivers delivering sediment separately to a shelf-margin canyon or merging together as they do today.
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影响因子：
5.3
作者：
Amidon, WH;Burbank, DW;Gehrels, GE
通讯作者：
Gehrels, GE
影响因子：
5.3
作者：
Galy, Valier;France-Lanord, Christian;Huyghe, Pascale
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Huyghe, Pascale
影响因子：
12.1
作者：
Blum, M.;Martin, J.;Garvin, M.
通讯作者：
Garvin, M.
影响因子：
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通讯作者：
Chen, L
影响因子：
2.9
作者：
Booth, AL;Zeitler, PK;Chamberlain, CP
通讯作者：
Chamberlain, CP