Continental-scale transport of sediments by the Baltic Ice Stream elucidated by coupled grain size and Nd provenance analyses
Continental-scale transport of sediments by the Baltic Ice Stream elucidated by coupled grain size and Nd provenance analyses
复制标题
通过耦合粒度和 Nd 来源分析阐明波罗的海冰流沉积物的大陆尺度输送
DOI：
10.1016/j.epsl.2018.03.017
复制
发表时间：
2018
影响因子：
5.3
通讯作者：
S. Hemming
中科院分区：
文献类型：
--
作者：
S. Boswell;S. Toucanne;T. Creyts;S. Hemming
我们介绍了一种确定亚冰川破碎和夹带沉积物的运移距离的方法。我们在波罗的海冰流末端边缘的沉积物上试验了这种方法，波罗的海冰流是芬诺斯坎迪亚冰盖在最后一次冰盛期最大的冰流。εND与环波罗的海河流沉积物的纬度之间有很强的相关性(R2=0.83)，这使我们能够使用εND作为校准距离的量度。次冰川搬运的沉积物在样品中的比例是根据粉砂组分(<；63μm)中的粒度比估计的。ε-ND和粒度联合分析揭示了波罗的海冰川沉积物的共同侵蚀来源，该沉积物位于奥兰基岩附近，在终端冰川上游850多公里处。这一结果与数值模拟和地貌研究的结果一致，与末次冰盛期之前快速流入波罗的海盆地的冰流相一致。这里介绍的方法可以用来推断晚更新世和早期冰川的冰川成因沉积物运移的距离。
We introduce a methodology for determining the transport distance of subglacially comminuted and entrained sediments. We pilot this method on sediments from the terminal margin of the Baltic Ice Stream, the largest ice stream of the Fennoscandian Ice Sheet during the Last Glacial Maximum. A strong correlation (R2= 0.83) between theεNd and latitudes of circum-Baltic river sediments enables us to useεNd as a calibrated measure of distance. The proportion of subglacially transported sediments in a sample is estimated from grain size ratios in the silt fraction (<63 μm). CoupledεNd and grain size analyses reveal a common erosion source for the Baltic Ice Stream sediments located near the Åland sill, more than 850 km upstream from the terminal moraines. This result is in agreement with both numerical modeling and geomorphological investigations of Fennoscandinavian erosion, and is consistent with rapid ice flow into the Baltic basins prior to the Last Glacial Maximum. The methodology introduced here could be used to infer the distances of glacigenic sediment transport from Late Pleistocene and earlier glaciations.
影响因子：
18.3
作者：
Rignot, Eric;Bamber, Jonathan L.;Van Meijgaard, Erik
通讯作者：
Van Meijgaard, Erik