Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice
ABSTRACT We have mapped the full crystallographic orientation of sea ice using electron backscatter diffraction (EBSD). This is the first time EBSD has been used to study sea ice. Platelet ice is a feature of sea ice near ice shelves. Ice crystals accumulate as an unconsolidated sub-ice platelet lay...
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/jog.2018.67 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000679 |
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crcambridgeupr:10.1017/jog.2018.67 2024-09-15T17:48:08+00:00 Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice WONGPAN, PAT PRIOR, DAVID J. LANGHORNE, PATRICIA J. LILLY, KATHERINE SMITH, INGA J. 2018 http://dx.doi.org/10.1017/jog.2018.67 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000679 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 64, issue 247, page 771-780 ISSN 0022-1430 1727-5652 journal-article 2018 crcambridgeupr https://doi.org/10.1017/jog.2018.67 2024-07-17T04:02:35Z ABSTRACT We have mapped the full crystallographic orientation of sea ice using electron backscatter diffraction (EBSD). This is the first time EBSD has been used to study sea ice. Platelet ice is a feature of sea ice near ice shelves. Ice crystals accumulate as an unconsolidated sub-ice platelet layer beneath the columnar ice (CI), where they are subsumed by the advancing sea–ice interface to form incorporated platelet ice (PI). As is well known, in CI the crystal preferred orientation comprises dominantly horizontal c -axes, while PI has c -axes varying between horizontal and vertical. For the first time, this study shows the a -axes of CI and PI are not random. Misorientation analysis has been used to illuminate the possible drivers of these alignments. In CI the misorientation angle distribution from random pairs and neighbour pairs of grains are indistinguishable, indicating the distributions are a consequence of crystal preferred orientation. Geometric selection during growth will develop the a -axis alignment in CI if ice growth in water is fastest parallel to the a -axis, as has previously been hypothesised. In contrast, in PI random-pair and neighbour-pair misorientation distributions are significantly different, suggesting mechanical rotation of crystals at grain boundaries as the most likely explanation. Article in Journal/Newspaper Antarc* Antarctic Ice Shelves Journal of Glaciology Sea ice Cambridge University Press Journal of Glaciology 64 247 771 780 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
ABSTRACT We have mapped the full crystallographic orientation of sea ice using electron backscatter diffraction (EBSD). This is the first time EBSD has been used to study sea ice. Platelet ice is a feature of sea ice near ice shelves. Ice crystals accumulate as an unconsolidated sub-ice platelet layer beneath the columnar ice (CI), where they are subsumed by the advancing sea–ice interface to form incorporated platelet ice (PI). As is well known, in CI the crystal preferred orientation comprises dominantly horizontal c -axes, while PI has c -axes varying between horizontal and vertical. For the first time, this study shows the a -axes of CI and PI are not random. Misorientation analysis has been used to illuminate the possible drivers of these alignments. In CI the misorientation angle distribution from random pairs and neighbour pairs of grains are indistinguishable, indicating the distributions are a consequence of crystal preferred orientation. Geometric selection during growth will develop the a -axis alignment in CI if ice growth in water is fastest parallel to the a -axis, as has previously been hypothesised. In contrast, in PI random-pair and neighbour-pair misorientation distributions are significantly different, suggesting mechanical rotation of crystals at grain boundaries as the most likely explanation. |
format |
Article in Journal/Newspaper |
author |
WONGPAN, PAT PRIOR, DAVID J. LANGHORNE, PATRICIA J. LILLY, KATHERINE SMITH, INGA J. |
spellingShingle |
WONGPAN, PAT PRIOR, DAVID J. LANGHORNE, PATRICIA J. LILLY, KATHERINE SMITH, INGA J. Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice |
author_facet |
WONGPAN, PAT PRIOR, DAVID J. LANGHORNE, PATRICIA J. LILLY, KATHERINE SMITH, INGA J. |
author_sort |
WONGPAN, PAT |
title |
Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice |
title_short |
Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice |
title_full |
Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice |
title_fullStr |
Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice |
title_full_unstemmed |
Using electron backscatter diffraction to measure full crystallographic orientation in Antarctic land-fast sea ice |
title_sort |
using electron backscatter diffraction to measure full crystallographic orientation in antarctic land-fast sea ice |
publisher |
Cambridge University Press (CUP) |
publishDate |
2018 |
url |
http://dx.doi.org/10.1017/jog.2018.67 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000679 |
genre |
Antarc* Antarctic Ice Shelves Journal of Glaciology Sea ice |
genre_facet |
Antarc* Antarctic Ice Shelves Journal of Glaciology Sea ice |
op_source |
Journal of Glaciology volume 64, issue 247, page 771-780 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2018.67 |
container_title |
Journal of Glaciology |
container_volume |
64 |
container_issue |
247 |
container_start_page |
771 |
op_container_end_page |
780 |
_version_ |
1810289255818199040 |