Understanding Himalayan erosion and the significance of the Nicobar Fan
Understanding Himalayan erosion and the significance of the Nicobar Fan
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DOI：
10.1016/j.epsl.2017.07.019
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发表时间：
2017-10
影响因子：
5.3
通讯作者：
L. McNeill;Brandon Dugan;Jan Backman;K. Pickering;H. Pouderoux;T. Henstock;K. Petronotis;Andrew Carter;F. Chemale;K. Milliken;Steffen Kutterolf;H. Mukoyoshi;Wenhuang Chen;S. Kachovich;F. Mitchison;S. Bourlange;T. Colson;M. Frederik;Gilles Guerin;M. Hamahashi;B. House;A. Hüpers;T. Jeppson;A. R. Kenigsberg;M. Kuranaga;N. Nair;S. Owari;Y. Shan;I. Song;Marta Torres;P. Vannucchi;P. Vrolijk;Tao Yang;Xixi Zhao;Ellen Thomas
中科院分区：
文献类型：
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作者：
L. McNeill;Brandon Dugan;Jan Backman;K. Pickering;H. Pouderoux;T. Henstock;K. Petronotis;Andrew Carter;F. Chemale;K. Milliken;Steffen Kutterolf;H. Mukoyoshi;Wenhuang Chen;S. Kachovich;F. Mitchison;S. Bourlange;T. Colson;M. Frederik;Gilles Guerin;M. Hamahashi;B. House;A. Hüpers;T. Jeppson;A. R. Kenigsberg;M. Kuranaga;N. Nair;S. Owari;Y. Shan;I. Song;Marta Torres;P. Vannucchi;P. Vrolijk;Tao Yang;Xixi Zhao;Ellen Thomas
要全面了解孟加拉-尼科巴扇系统，需要对尼科巴扇的完整沉积部分进行采样，这是国际海洋发现计划 (IODP) 北苏门答腊岛以西的 362 号探险队首次实现的。我们发现沉积物堆积率（SAR）从∼9.5 Ma开始明显上升，并在9.5-2 Ma区间达到250-350 m/Myr，这等于或远远超过类似纬度的孟加拉扇的沉积物堆积率。 SAR 的显着上升和来自喜马拉雅山的持续来源需要对孟加拉-尼科巴海底扇中的沉积物路径进行重大重组。这与东喜马拉雅西隆高原的反转和向西传播的印缅楔体的侵蚀相吻合，这减少了大陆可容纳空间并增加了直接向扇的沉积物供应。我们的研究结果挑战了一种普遍持有的观点，即孟加拉-尼科巴海底扇中沉积物通量的变化是由作用于喜马拉雅-青藏高原的离散构造或气候事件引起的。相反，构造和气候过程的相互作用导致扇系统的发展是间断的变化而不是逐渐的进展。
A holistic view of the Bengal–Nicobar Fan system requires sampling the full sedimentary section of the Nicobar Fan, which was achieved for the first time by International Ocean Discovery Program (IODP) Expedition 362 west of North Sumatra. We identified a distinct rise in sediment accumulation rate (SAR) beginning ∼9.5 Ma and reaching 250–350 m/Myr in the 9.5–2 Ma interval, which equal or far exceed rates on the Bengal Fan at similar latitudes. This marked rise in SAR and a constant Himalayan-derived provenance necessitates a major restructuring of sediment routing in the Bengal–Nicobar submarine fan. This coincides with the inversion of the Eastern Himalayan Shillong Plateau and encroachment of the west-propagating Indo–Burmese wedge, which reduced continental accommodation space and increased sediment supply directly to the fan. Our results challenge a commonly held view that changes in sediment flux seen in the Bengal–Nicobar submarine fan were caused by discrete tectonic or climatic events acting on the Himalayan–Tibetan Plateau. Instead, an interplay of tectonic and climatic processes caused the fan system to develop by punctuated changes rather than gradual progradation.