Ploughing of subglacial sediment
Abstract Mechanical conditions at the base of Trapridge Glacier, Yukon Territory, were investigated using a “ploughmeter”. We describe the physical characteristics and the theory of this new instrument as well as its operation. Observational results reveal variations in ploughmeter response that mig...
Published in: | Journal of Glaciology |
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Language: | English |
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Cambridge University Press (CUP)
1994
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Online Access: | http://dx.doi.org/10.1017/s0022143000003853 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000003853 |
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crcambridgeupr:10.1017/s0022143000003853 2024-09-15T18:15:38+00:00 Ploughing of subglacial sediment Fischer, URS H. Clarke, Garry K. C. 1994 http://dx.doi.org/10.1017/s0022143000003853 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000003853 en eng Cambridge University Press (CUP) Journal of Glaciology volume 40, issue 134, page 97-106 ISSN 0022-1430 1727-5652 journal-article 1994 crcambridgeupr https://doi.org/10.1017/s0022143000003853 2024-08-28T04:00:57Z Abstract Mechanical conditions at the base of Trapridge Glacier, Yukon Territory, were investigated using a “ploughmeter”. We describe the physical characteristics and the theory of this new instrument as well as its operation. Observational results reveal variations in ploughmeter response that might be attributed to spatial variability in subglacial processes or spatial variation in sediment granulometry. Quantitative analysis of the interaction of the ploughmeter with the basal layer yields estimates of rheological parameters. If the sediment is assumed to behave as a Newtonian viscous fluid, the estimated effective viscosity is 3.0 × 10 9 −3.1 × 10 10 Pas; if it is assumed to behave as an ideal plastic solid, the estimated yield strength is 48–57 kPa. In both cases, the estimated shear resistance of subglacial material is comparable to but somewhat less than that required to balance fully the applied basal shear stress. Article in Journal/Newspaper Journal of Glaciology Yukon Cambridge University Press Journal of Glaciology 40 134 97 106 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract Mechanical conditions at the base of Trapridge Glacier, Yukon Territory, were investigated using a “ploughmeter”. We describe the physical characteristics and the theory of this new instrument as well as its operation. Observational results reveal variations in ploughmeter response that might be attributed to spatial variability in subglacial processes or spatial variation in sediment granulometry. Quantitative analysis of the interaction of the ploughmeter with the basal layer yields estimates of rheological parameters. If the sediment is assumed to behave as a Newtonian viscous fluid, the estimated effective viscosity is 3.0 × 10 9 −3.1 × 10 10 Pas; if it is assumed to behave as an ideal plastic solid, the estimated yield strength is 48–57 kPa. In both cases, the estimated shear resistance of subglacial material is comparable to but somewhat less than that required to balance fully the applied basal shear stress. |
format |
Article in Journal/Newspaper |
author |
Fischer, URS H. Clarke, Garry K. C. |
spellingShingle |
Fischer, URS H. Clarke, Garry K. C. Ploughing of subglacial sediment |
author_facet |
Fischer, URS H. Clarke, Garry K. C. |
author_sort |
Fischer, URS H. |
title |
Ploughing of subglacial sediment |
title_short |
Ploughing of subglacial sediment |
title_full |
Ploughing of subglacial sediment |
title_fullStr |
Ploughing of subglacial sediment |
title_full_unstemmed |
Ploughing of subglacial sediment |
title_sort |
ploughing of subglacial sediment |
publisher |
Cambridge University Press (CUP) |
publishDate |
1994 |
url |
http://dx.doi.org/10.1017/s0022143000003853 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000003853 |
genre |
Journal of Glaciology Yukon |
genre_facet |
Journal of Glaciology Yukon |
op_source |
Journal of Glaciology volume 40, issue 134, page 97-106 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000003853 |
container_title |
Journal of Glaciology |
container_volume |
40 |
container_issue |
134 |
container_start_page |
97 |
op_container_end_page |
106 |
_version_ |
1810453503195217920 |