气候变化领域集成服务门户(CCPortal): The subglacial mosaic of the Laurentide Ice Sheet; a study of the interior region of southwestern Hudson Bay

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DOI	10.1016/j.quascirev.2019.04.015
	The subglacial mosaic of the Laurentide Ice Sheet; a study of the interior region of southwestern Hudson Bay
	Gauthier M.S.; Hodder T.J.; Ross M.; Kelley S.E.; Rochester A.; McCausland P.
发表日期	2019
ISSN	0277-3791
起始页码	1
结束页码	27
卷号	214
英文摘要	Reconstructions of past ice-flow provide useful insights into the long-term behaviour of past ice sheets and help to understand how glaciated landscapes are shaped. Here, we present reconstruction of a 10-phase ice-flow history from southwestern Hudson Bay in northeastern Manitoba (Canada), a dynamic region situated between two major ice dispersal centres of the Laurentide Ice Sheet. We utilize a diverse geologic dataset including 1900 field-based erosional indicators, 12 streamlined-landform flowsets, esker and meltwater corridor orientations, 103 till-fabrics analyses, and 1344 till-clast lithology counts. Our reconstruction suggests that both pre-MIS 2 and MIS 2 glaciations followed similar growth patterns, where ice advanced into study area from ice centered to the east (probably in northern Quebec), followed by a switch in ice-flow direction indicating flow from the Keewatin ice centre to the northwest and north. The cause for this switch in ice-flow orientation is uncertain, but the youngest switch may relate to retreat of ice during MIS 3 that then left space for Keewatin-sourced ice to advance over the study area. While modelling experiments indicate widespread cold-based conditions in the study area during the last glacial cycle, uniformly relict landscapes are not common. Instead, the glaciated landscape is palimpsest and commonly fragmented, forming a subglacial bed mosaic of erosional and depositional assemblages that record both shifting ice-flow direction through time and shifting subglacial conditions. Each assemblage formed, or modified, during times of dynamic (warm-based) ice, and later preserved under conditions below or close to the pressure melting point (slow and sluggish, or cold-based). © 2019 Elsevier Ltd
英文关键词	Data analysis; Data treatment; Geomorphology; Glacial; Glaciology; Hudson Bay Lowland; Inheritance; Laurentide Ice Sheet; North America; Paleogeography; Palimpsest; Quaternary
语种	英语
scopus关键词	Data reduction; Erosion; Geomorphology; Glacial geology; Glaciers; Landforms; Lithology; Data treatment; Glacial; Glaciology; Hudson Bay; Inheritance; Laurentide ice sheets; North America; Paleogeography; Palimpsest; Quaternary; Ice; data assimilation; geomorphology; ice flow; Laurentide Ice Sheet; marine isotope stage; meltwater; paleogeography; reconstruction; sea ice; snowmelt; subglacial environment; Canada; Hudson Bay; Keewatin; Manitoba; Nunavut; Quebec [Canada]
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/151926
作者单位	Manitoba Geological Survey, Manitoba Growth, Enterprise and Trade, 360-1395 Ellice Avenue, Winnipeg, R3G 3P2, Canada; Department of Earth and Environmental Sciences, University of WaterlooOntario N2L 3G1, Canada; Western Paleomagnetic and Petrophysical Laboratory, Western University, London, Ontario N6A 5B7, Canada
推荐引用方式 GB/T 7714	Gauthier M.S.,Hodder T.J.,Ross M.,et al. The subglacial mosaic of the Laurentide Ice Sheet; a study of the interior region of southwestern Hudson Bay[J],2019,214.
APA	Gauthier M.S.,Hodder T.J.,Ross M.,Kelley S.E.,Rochester A.,&McCausland P..(2019).The subglacial mosaic of the Laurentide Ice Sheet; a study of the interior region of southwestern Hudson Bay.Quaternary Science Reviews,214.
MLA	Gauthier M.S.,et al."The subglacial mosaic of the Laurentide Ice Sheet; a study of the interior region of southwestern Hudson Bay".Quaternary Science Reviews 214(2019).