A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier
Abstract The rate of strain tensor at a point on the surface of a glacier may be determined by setting up a number of stakes in a pattern and measuring the rate of change of the distances between them. A suitable pattern consists of four stakes at the corners of a square with one stake at the center...
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Cambridge University Press (CUP)
1959
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Online Access: | http://dx.doi.org/10.1017/s0022143000017093 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000017093 |
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crcambridgeupr:10.1017/s0022143000017093 2024-06-23T07:53:04+00:00 A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier Nye, J. F. 1959 http://dx.doi.org/10.1017/s0022143000017093 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000017093 en eng Cambridge University Press (CUP) Journal of Glaciology volume 3, issue 25, page 409-419 ISSN 0022-1430 1727-5652 journal-article 1959 crcambridgeupr https://doi.org/10.1017/s0022143000017093 2024-06-05T04:04:59Z Abstract The rate of strain tensor at a point on the surface of a glacier may be determined by setting up a number of stakes in a pattern and measuring the rate of change of the distances between them. A suitable pattern consists of four stakes at the corners of a square with one stake at the center. Five such patterns were used on Austerdalsbreen, Norway, in August 1956. The problem is to deduce the best values of the 3 independent components of the strain-rate tensor from the 8 measured quantities, and, for this purpose, a least-squares method, invented by Bond for the analogous problem in crystal physics, is used. The principal strain-rates are found to within about ±0.005 yr. −1 and their directions relative to the stake system to within about ±0.5°. The directions and magnitudes of the principal stresses are then deduced from Glen’s flow law and a suitable general theory. The directions of the principal strain-rates are in good agreement with the directions of the crevasses, but the experiment is inconclusive on the question of the magnitude of the stress needed to form a crevasse. Article in Journal/Newspaper glacier Journal of Glaciology Cambridge University Press Norway Journal of Glaciology 3 25 409 419 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract The rate of strain tensor at a point on the surface of a glacier may be determined by setting up a number of stakes in a pattern and measuring the rate of change of the distances between them. A suitable pattern consists of four stakes at the corners of a square with one stake at the center. Five such patterns were used on Austerdalsbreen, Norway, in August 1956. The problem is to deduce the best values of the 3 independent components of the strain-rate tensor from the 8 measured quantities, and, for this purpose, a least-squares method, invented by Bond for the analogous problem in crystal physics, is used. The principal strain-rates are found to within about ±0.005 yr. −1 and their directions relative to the stake system to within about ±0.5°. The directions and magnitudes of the principal stresses are then deduced from Glen’s flow law and a suitable general theory. The directions of the principal strain-rates are in good agreement with the directions of the crevasses, but the experiment is inconclusive on the question of the magnitude of the stress needed to form a crevasse. |
format |
Article in Journal/Newspaper |
author |
Nye, J. F. |
spellingShingle |
Nye, J. F. A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier |
author_facet |
Nye, J. F. |
author_sort |
Nye, J. F. |
title |
A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier |
title_short |
A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier |
title_full |
A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier |
title_fullStr |
A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier |
title_full_unstemmed |
A Method of Determining the Strain-Rate Tensor at the Surface of a Glacier |
title_sort |
method of determining the strain-rate tensor at the surface of a glacier |
publisher |
Cambridge University Press (CUP) |
publishDate |
1959 |
url |
http://dx.doi.org/10.1017/s0022143000017093 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000017093 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
glacier Journal of Glaciology |
genre_facet |
glacier Journal of Glaciology |
op_source |
Journal of Glaciology volume 3, issue 25, page 409-419 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000017093 |
container_title |
Journal of Glaciology |
container_volume |
3 |
container_issue |
25 |
container_start_page |
409 |
op_container_end_page |
419 |
_version_ |
1802644543556812800 |