Access of surface meltwater to beds of sub-freezing glaciers: preliminary insights

被引：114

作者：

Alley, RB ^{[1
]}

Dupont, TK ^{[1
]}

Parizek, BR ^{[1
]}

Anandakrishnan, S ^{[1
]}

机构：

[1] Penn State Univ, Dept Geosci & EMS EESI, University Pk, PA 16802 USA

来源：

ANNALS OF GLACIOLOGY, VOL 40, 2005 | 2005年 / 40卷

关键词：

D O I：

10.3189/172756405781813483

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Sufficiently deep water-filled fractures can penetrate even cold ice-sheet ice, but glaciogenic stresses are typically smaller than needed to propagate water-filled fractures that are less than a few tens of meters deep, as shown by our simplified analytical treatment based on analogous models of magmatic processes. However, water-filled fractures are inferred to reach the bed of Greenland through > 1 km of ice and then collapse to form moulins, which are observed. Supraglacial lakes appear especially important among possible crack 'nucleation' mechanisms, because lakes can warm ice, supply water, and increase the pressure driving water flow and ice cracking.

引用

页码：8 / 14

页数：7

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