气候变化领域集成服务门户(CCPortal): Compositional changes in deglacial red mud event beds off the Laurentian Channel reveal source mixing; grain-size partitioning and ice retreat

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DOI	10.1016/j.quascirev.2019.04.031
	Compositional changes in deglacial red mud event beds off the Laurentian Channel reveal source mixing; grain-size partitioning and ice retreat
	Leng W.; von Dobeneck T.; Just J.; Govin A.; St-Onge G.; Piper D.J.W.
发表日期	2019
ISSN	0277-3791
起始页码	98
结束页码	115
卷号	215
英文摘要	Between 22 and 17 cal ka BP, five large meltwater events from within the Laurentian Channel Ice Stream deposited mud beds meters thick across a large area of the Laurentian Fan and adjacent continental slopes. This study determines the sources of these event beds and relates them to the glaciological evolution of the retreating Laurentian Ice Stream. We analyzed major element and magnetic mineral contents of these event beds and compare them with a new collection of 80 source reference samples from the Gulf of St. Lawrence area. Element ratios suggest a steady compositional change from older to younger outburst event beds, while element-specific offsets from reference sample compositions indicate grain-size and mineral/element partitioning during suspension transport. Their magnetic properties place event beds on the source mixing trend of four reference samples groups, which represent two magnetite-rich sources (Canadian Shield and/or Southern Newfoundland) and two hematite-rich sources (Appalachian red beds). Using a deterministic linear source mixing model based on IRM100mT, HIRM and Ca%, we find that the earlier two outburst events had higher contributions from granitic and calcareous sources than the later three events. Combining materials, timing and scenarios of the outburst events with ice-sheet retreat and ice-stream dynamics, we argue that the subglacial sediment depocenter of the earlier two event beds was located in the lower Laurentian Channel while that of the later three events was upstream from Cabot Strait. © 2019
英文关键词	Environmental Magnetism; Gulf of St. Lawrence; Laurentian Channel Ice Stream; Major element analysis; North Atlantic; Paleoceanography; Provenance study; Quaternary; Sedimentology-marine cores; Subglacial outburst floods
语种	英语
scopus关键词	Carrier concentration; Grain size and shape; Hematite; Magnetism; Magnetite; Mixing; Environmental magnetism; Gulf of St. Lawrence; Ice streams; Major elements; Marine cores; North Atlantic; Outburst floods; Paleoceanography; Provenance studies; Quaternary; Ice; continental slope; core analysis; deglaciation; geomagnetism; glacial hydrology; ice retreat; Laurentide Ice Sheet; magnetic mineral; outburst; paleoceanography; provenance; red soil; subglacial deposit; Atlantic Ocean; Atlantic Ocean (North); Cabot Strait; Canada; Canadian Shield; Gulf of Saint Lawrence; Laurentian Channel; Newfoundland; Newfoundland and Labrador
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151910
作者单位	MARUM-Center for Marine Environmental Sciences and Faculty of Geosciences, University of Bremen, Bremen, Germany; LSCE/IPSL, Laboratoire des Sciences Du Climat et de L'Environnement (CEA-CNRS-UVSQ), Université Paris-Saclay, Gif-Sur-Yvette, 91190, France; Institut des Sciences de La Mer de Rimouski (ISMER), Canada Research Chair in Marine Geology, Université Du Québec à Rimouski and GEOTOP, Rimouski, QC, Canada; Natural Resources Canada, Geological Survey of Canada, Bedford Institute of Oceanography, Dartmouth, NS, Canada
推荐引用方式 GB/T 7714	Leng W.,von Dobeneck T.,Just J.,et al. Compositional changes in deglacial red mud event beds off the Laurentian Channel reveal source mixing; grain-size partitioning and ice retreat[J],2019,215.
APA	Leng W.,von Dobeneck T.,Just J.,Govin A.,St-Onge G.,&Piper D.J.W..(2019).Compositional changes in deglacial red mud event beds off the Laurentian Channel reveal source mixing; grain-size partitioning and ice retreat.Quaternary Science Reviews,215.
MLA	Leng W.,et al."Compositional changes in deglacial red mud event beds off the Laurentian Channel reveal source mixing; grain-size partitioning and ice retreat".Quaternary Science Reviews 215(2019).