DOI: 10.1038/ngeo3012
论文题名: Anatomy of a meltwater drainage system beneath the ancestral East Antarctic ice sheet
作者: Simkins L.M. ; Anderson J.B. ; Greenwood S.L. ; Gonnermann H.M. ; Prothro L.O. ; Halberstadt A.R.W. ; Stearns L.A. ; Pollard D. ; DeConto R.M.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2017
卷: 10, 期: 9 起始页码: 691
结束页码: 697
语种: 英语
Scopus关键词: basal melting
; channel flow
; drainage network
; glacial hydrology
; grounding line
; heat flux
; ice sheet
; ice stream
; meltwater
; sedimentation
; streamflow
; Antarctic Ice Sheet
; Antarctica
; East Antarctic Ice Sheet
; East Antarctica
; Ross Sea
; Southern Ocean
英文摘要: Subglacial hydrology is critical to understand the behaviour of ice sheets, yet active meltwater drainage beneath contemporary ice sheets is rarely accessible to direct observation. Using geophysical and sedimentological data from the deglaciated western Ross Sea, we identify a palaeo-subglacial hydrological system active beneath an area formerly covered by the East Antarctic ice sheet. A long channel network repeatedly delivered meltwater to an ice stream grounding line and was a persistent pathway for episodic meltwater drainage events. Embayments within grounding-line landforms coincide with the location of subglacial channels, marking reduced sedimentation and restricted landform growth. Consequently, channelized drainage at the grounding line influenced the degree to which these landforms could provide stability feedbacks to the ice stream. The channel network was connected to upstream subglacial lakes in an area of geologically recent rifting and volcanism, where elevated heat flux would have produced sufficient basal melting to fill the lakes over decades to several centuries; this timescale is consistent with our estimates of the frequency of drainage events at the retreating grounding line. Based on these data, we hypothesize that ice stream dynamics in this region were sensitive to the underlying hydrological system. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/105716
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: Department of Earth, Environment and Planetary Sciences, Rice University, Houston, TX, United States; Department of Geological Sciences, Stockholm University, Stockholm, Sweden; Department of Geosciences, University of Massachusetts, Amherst, MA, United States; Department of Geology, University of Kansas, Lawrence, KS, United States; Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA, United States
Recommended Citation:
Simkins L.M.,Anderson J.B.,Greenwood S.L.,et al. Anatomy of a meltwater drainage system beneath the ancestral East Antarctic ice sheet[J]. Nature Geoscience,2017-01-01,10(9)