Understanding Himalayan erosion and the significance of the Nicobar Fan

TitleUnderstanding Himalayan erosion and the significance of the Nicobar Fan
Publication TypeJournal Article
Year of Publication2017
AuthorsMcNeill LC, Dugan B, Backman J, Pickering KT, Pouderoux HFA, Henstock TJ, Petronotis KE, Carter A, Chemale, Jr F, Milliken KL, Kutterolf S, Mukoyoshi H, Chen W, Kachovich S, Mitchison FL, Bourlange S, Colson TA, Frederik MCG, Guerin G, Hamahashi M, House BM, Huepers A, Jeppson TN, Kenigsberg AR, Kuranaga M, Nair N, Owari S, Shan Y, Song I, Torres ME, Vannucchi P, Vrolijk PJ, Yang T, Zhao X, Thomas E
JournalEarth and Planetary Science Letters
Date Published10/2017

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 similar to 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.