气候变化领域集成服务门户(CCPortal): Antarctic blue-ice moraines: Analogue for Northern Hemisphere ice sheets?

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DOI	10.1016/j.quascirev.2020.106620
	Antarctic blue-ice moraines: Analogue for Northern Hemisphere ice sheets?
	Sugden D.; Hall A.
发表日期	2020
ISSN	0277-3791
卷号	249
英文摘要	This paper reviews the distribution, character and age of blue-ice moraines in Antarctica and asks whether there are implications for the study of former Pleistocene ice sheets in the Northern Hemisphere. Blue-ice forms where acceleration of downslope katabatic winds removes snow and causes ice to ablate. Upward ice flow compensates for the surface ablation and in some places brings rock debris to the surface to form a blue-ice moraine. Blue-ice moraines occur where topography focuses katabatic winds, notably outlet glaciers cutting through mountains and in the lee of nunataks and escarpments nearer the coast. Many Antarctic blue-ice moraines have been accumulating for millions of years. The cyclic growth and decay of Pleistocene ice sheets and the dominance of surface ablation near the ice-sheet margins are clearly different, yet there are aspects that apply to Pleistocene ice sheets. Based on Antarctic blue-ice deposits, equivalent deposits associated with former Pleistocene ice sheets are likely to: (1) lie in topographic sediment traps such as in side valleys or embayments next to outlet glaciers, (2) occur in the lee of mountains, (3) display a morphology indicating ice flow into the embayment or towards the mountain front, (4) include a wide range of lithologies derived from the inland ice sheet, yet consist wholly of local debris in places, (5) accumulate a thick deposit perhaps over successive glaciations. Further, (6) the location and intensity of moraine formation will change spatially and vertically in response to changes in the relative elevation of the surrounding mountains and its effect on ice flow. The extent to which these criteria will help in interpreting the behaviour of Pleistocene ice sheets is uncertain. But we use examples from the Greenland, Laurentide and Eurasian ice sheets to suggest that the concept of enhanced ablation by katabatic winds encouraging surface moraine formation helps resolve several puzzles. © 2020 Elsevier Ltd
英文关键词	Antarctica; Blue-ice moraines; Geomorphology; Glaciology; Greenland; Northern Hemisphere ice sheets; Pleistocene; Topographic sediment traps
语种	英语
scopus关键词	Ablation; Debris; Deposits; Glacial geology; Glaciers; Landforms; Topography; Wind; Antarctica; Cyclic growth; Greenland; Katabatic winds; Northern Hemispheres; Pleistocene; Surface ablation; Thick deposit; Ice; ablation; acceleration; ice flow; ice sheet; Laurentide Ice Sheet; moraine; Northern Hemisphere; Pleistocene; snow accumulation; topography; Antarctica; Arctic; Eurasia; Greenland
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/151239
作者单位	School of GeoSciences, University of Edinburgh, Edinburgh, EH8 9XP, United Kingdom; Department of Physical Geography, Stockholm University, Stockholm, 10691, United Kingdom
推荐引用方式 GB/T 7714	Sugden D.,Hall A.. Antarctic blue-ice moraines: Analogue for Northern Hemisphere ice sheets?[J],2020,249.
APA	Sugden D.,&Hall A..(2020).Antarctic blue-ice moraines: Analogue for Northern Hemisphere ice sheets?.Quaternary Science Reviews,249.
MLA	Sugden D.,et al."Antarctic blue-ice moraines: Analogue for Northern Hemisphere ice sheets?".Quaternary Science Reviews 249(2020).