Thickness and extent of the subglacial till layer beneath an Antarctic paleo-ice stream

被引：163

作者：

Dowdeswell, JA ^{[1
]}

O Cofaigh, C

Pudsey, CJ

机构：

[1] Univ Cambridge, Scott Polar Res Inst, Cambridge CB2 1ER, England

[2] British Antarctic Survey, Cambridge CB3 0ET, England

来源：

GEOLOGY | 2004年 / 32卷 / 01期

关键词：

paleo-ice streams; subglacial environment; deformation till; Antarctic Peninsula; Quaternary;

D O I：

10.1130/G19864.1

中图分类号：

P5 [地质学];

学科分类号：

0709 ; 081803 ;

摘要：

Fast-flowing ice streams and outlet glaciers currently account for as much as 90% of the discharge from the Antarctic and Greenland Ice Sheets. Although the deformation of subglacial material has been proposed as the mechanism for this rapid motion, such sediment is usually hidden under several kilometers of ice. Marine-geophysical records have allowed reconstruction of the three-dimensional thickness of the sedimentary bed beneath a large Antarctic paleo-ice stream for the first time. Fast flow is indicated by streamlined seafloor lineations that form the surface of a layer of low shear strength, unsorted sediment, averaging 4.6 m thick. Rapid motion of the paleo-ice stream was a result of subglacial deformation within this layer.

引用

页码：13 / 16

页数：4

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