Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard
Abstract Recent mapping of ice-surface and bedrock topography from airborne radio-echo sounding has shown that the ice caps of Nordaustlandet, Svalbard, are divided into a series of well-defined drainage basins. Three lines of evidence indicate that several distinctive modes of ice-flow regime chara...
Published in: | Journal of Glaciology |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1986
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0022143000006845 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006845 |
id |
crcambridgeupr:10.1017/s0022143000006845 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/s0022143000006845 2024-09-15T18:07:58+00:00 Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard Dowdeswell, Julian A. 1986 http://dx.doi.org/10.1017/s0022143000006845 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006845 en eng Cambridge University Press (CUP) Journal of Glaciology volume 32, issue 110, page 31-38 ISSN 0022-1430 1727-5652 journal-article 1986 crcambridgeupr https://doi.org/10.1017/s0022143000006845 2024-07-31T04:01:29Z Abstract Recent mapping of ice-surface and bedrock topography from airborne radio-echo sounding has shown that the ice caps of Nordaustlandet, Svalbard, are divided into a series of well-defined drainage basins. Three lines of evidence indicate that several distinctive modes of ice-flow regime characterize these basins: (1) comparison between observed and theoretical ice-surface profiles; (2) analysis of driving stresses; and (3) observations of ice-surface features on satellite imagery and air photographs. The drainage basins are inferred to behave in the following ways. First, basins with low driving stresses and surface profiles, some of them clearly stagnant, are associated with the quiescent phase between glacier surges. Secondly, the ice streams draining southern Vestfonna have low surface profiles, relatively low driving stresses, and marked shear zones at their margins. They are interpreted to be flowing continuously at a relatively faster rate than the ridges between them. Basal melting, perhaps combined with substrate deformation, is probably responsible for the regime of these glaciers. Thirdly, the remaining basins studied on Nordaustlandet have relatively high marginal driving stresses and high surface profiles. They are interpreted to be frozen to their beds, at least near their margins. Some of these basins may also surge, particularly those where a part of the basin is below sea-level, and therefore is probably underlain by considerable thicknesses of deformable sediments. Article in Journal/Newspaper glacier Journal of Glaciology Nordaustlandet Svalbard Vestfonna Cambridge University Press Journal of Glaciology 32 110 31 38 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Abstract Recent mapping of ice-surface and bedrock topography from airborne radio-echo sounding has shown that the ice caps of Nordaustlandet, Svalbard, are divided into a series of well-defined drainage basins. Three lines of evidence indicate that several distinctive modes of ice-flow regime characterize these basins: (1) comparison between observed and theoretical ice-surface profiles; (2) analysis of driving stresses; and (3) observations of ice-surface features on satellite imagery and air photographs. The drainage basins are inferred to behave in the following ways. First, basins with low driving stresses and surface profiles, some of them clearly stagnant, are associated with the quiescent phase between glacier surges. Secondly, the ice streams draining southern Vestfonna have low surface profiles, relatively low driving stresses, and marked shear zones at their margins. They are interpreted to be flowing continuously at a relatively faster rate than the ridges between them. Basal melting, perhaps combined with substrate deformation, is probably responsible for the regime of these glaciers. Thirdly, the remaining basins studied on Nordaustlandet have relatively high marginal driving stresses and high surface profiles. They are interpreted to be frozen to their beds, at least near their margins. Some of these basins may also surge, particularly those where a part of the basin is below sea-level, and therefore is probably underlain by considerable thicknesses of deformable sediments. |
format |
Article in Journal/Newspaper |
author |
Dowdeswell, Julian A. |
spellingShingle |
Dowdeswell, Julian A. Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard |
author_facet |
Dowdeswell, Julian A. |
author_sort |
Dowdeswell, Julian A. |
title |
Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard |
title_short |
Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard |
title_full |
Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard |
title_fullStr |
Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard |
title_full_unstemmed |
Drainage-Basin Characteristics of Nordaustlandet Ice Caps, Svalbard |
title_sort |
drainage-basin characteristics of nordaustlandet ice caps, svalbard |
publisher |
Cambridge University Press (CUP) |
publishDate |
1986 |
url |
http://dx.doi.org/10.1017/s0022143000006845 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006845 |
genre |
glacier Journal of Glaciology Nordaustlandet Svalbard Vestfonna |
genre_facet |
glacier Journal of Glaciology Nordaustlandet Svalbard Vestfonna |
op_source |
Journal of Glaciology volume 32, issue 110, page 31-38 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000006845 |
container_title |
Journal of Glaciology |
container_volume |
32 |
container_issue |
110 |
container_start_page |
31 |
op_container_end_page |
38 |
_version_ |
1810445320809611264 |