当前位置: X-MOL 学术Mar. Petrol. Geol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Sedimentary provenance of the Plio-Pleistocene Nicobar Fan: Complex sourcing revealed through Raman spectroscopy heavy mineral analysis
Marine and Petroleum Geology ( IF 3.7 ) Pub Date : 2020-12-18 , DOI: 10.1016/j.marpetgeo.2020.104874
Max Webb , Amy Gough , Paola Vannucchi , Nils K. Lünsdorf , Joseph McNeil

The Nicobar Fan lies within the north-eastern Indian Ocean between the Ninety-East Ridge and Sunda Arc. The fan forms part of the Bengal–Nicobar Fan System and is among the oldest and largest submarine fans on Earth. Previous U–Pb zircon studies of the Nicobar and Bengal fans indicate the Himalaya as the dominate sediment source, making these fans a major Cenozoic sink for uplifted Himalayan sediment. However, the northwards moving Indian Plate, coupled with mid-Pleistocene collision of the Ninety-East Ridge with the Sunda Arc, has shutdown many sediment pathways linking the Himalaya and Nicobar Fan. Here we use big data Raman spectroscopy heavy mineral analysis along with U–Pb zircon data to better define sediment source regions for the Nicobar Fan during the Plio-Pleistocene following the shutdown of sediment delivery. The detrital zircon spectra for the Plio-Pleistocene Nicobar Fan from this study are consistent with previous work indicating that the original sources of these zircons can be found within both the Greater and Tethyan Himalaya, the Gangdese Arc, and the Indo-Myanmar Ranges. However, the heavy mineral data indicate that a large proportion of sediment has been derived from a more complex array of sources. This is coupled with an abundance of low- and moderate-stability minerals (e.g., amphibole, apatite, clinopyroxene), which are unlikely to have been transported large distances. Suggesting that proximal sources have delivered the majority of lower-stability heavy minerals into the Plio-Pleistocene Nicobar Fan. We show that from the Pleistocene onwards direct sediment delivery into the Nicobar Fan from the Himalaya was largely shutdown, with sediment instead shedding off the uplifting Indo-Myanmar Ranges, the Andaman–Nicobar Accretionary Ridge, and the westwards propagating Ayeyarwady River. This study shows that extensive uplift along the northern Sunda Arc is recorded in the Nicobar Fan alongside the previously reported Himalayan record.



中文翻译:

上新世更新世尼古巴扇的沉积物来源:通过拉曼光谱法重矿物分析揭示了复杂的来源

尼科巴迷(Nicobar Fan)位于印度洋东北部,位于九十东岭和Sun达弧之间。风扇是孟加拉–尼科巴风扇系统的一部分,是地球上最古老,最大的海底风扇之一。先前对尼古巴和孟加拉扇的锆石研究表明,喜马拉雅山是主要的沉积物来源,使这些扇成为喜马拉雅沉积物隆升的主要新生代汇。但是,向北移动的印度板块,再加上九十东脊与Sun他弧的更新世中期碰撞,已经关闭了连接喜马拉雅山和尼科巴扇的许多沉积物路径。在这里,我们使用大数据拉曼光谱重矿物分析以及U–Pb锆石数据来更好地定义在沉积物输送停止后的上新世上新世期间尼古巴扇的沉积物来源区域。这项研究中的上新世更新世尼古巴扇的碎屑锆石光谱与先前的工作一致,表明这些锆石的原始来源可以在大特提斯和喜提雅喜马拉雅山,冈底斯弧和印度-缅甸山脉中找到。但是,大量的矿物数据表明,很大比例的沉积物来自更复杂的来源。再加上大量低稳定性和中等稳定性的矿物(例如角闪石,磷灰石,斜柏石),这些矿物不太可能远距离运输。这表明近端来源已​​将大部分稳定性较差的重矿物输送至上新世新世古尼古巴扇。我们显示,从更新世开始,从喜马拉雅山直接进入Nicobar Fan的沉积物被大量关闭,相反,沉积物从隆起的印度缅甸山脉,安达曼尼科巴增生岭和向西蔓延的伊洛瓦底江中流失。这项研究表明,尼科巴扇形卫星记录了沿着Sun他弧北部的大范围隆升,同时记录了先前报道的喜马拉雅记录。

更新日期:2020-12-28
down
wechat
bug