Microstructural evolution of ice under simple shear deformation
To investigate microstructure in ice deformed under simple shear conditions experiments were performed with artificial polycrystalline ice and natural ice samples form Vatnajökull glacier in Iceland. A new deformation apparatus was tested and results from deformation were compared to literature to v...
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ftunivgoeteborg:oai:gupea.ub.gu.se:2077/67219 2023-10-29T02:36:30+01:00 Microstructural evolution of ice under simple shear deformation Liebl, Carina University of Gothenburg/Department of Earth Sciences Göteborgs universitet/Institutionen för geovetenskaper 2021-01-11 application/pdf http://hdl.handle.net/2077/67219 eng eng B 1120 http://hdl.handle.net/2077/67219 Text H2 Student essay 2021 ftunivgoeteborg 2023-10-04T21:16:00Z To investigate microstructure in ice deformed under simple shear conditions experiments were performed with artificial polycrystalline ice and natural ice samples form Vatnajökull glacier in Iceland. A new deformation apparatus was tested and results from deformation were compared to literature to validate the method. Boundary conditions for deformation were varied. Experiments were performed at -5°C and -10°C and three strain rates were applied (2.5x10-7 1/s, 1.25x10-6 1/s, 2.5x10-6 1/s). It is shown that the natural samples, which contain only 2-3 grains, provide a close-up image on specific situation. This gives the opportunity to study them in detail. A special focus is set on the behaviour of grain boundaries during deformation. A preferred arrangement with at least one side of the boundary close to a prism face is seen. While in warm or slow deformations a tendency to favour boundaries with a combination of {1̅ 1̅ 22} and {101̅ 2} faces. The type of crystall face and their orientation towards deformation direction befor deformation has an major influence on the development during deformation. Brittle fractures were observed in the samples, which immediately filled with small new grains. This was only observed in samples deformed at -10°C but no dependency to strain rate was oberved. Text glacier Iceland Vatnajökull University of Gothenburg: GUPEA (Gothenburg University Publications Electronic Archive) |
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Open Polar |
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University of Gothenburg: GUPEA (Gothenburg University Publications Electronic Archive) |
op_collection_id |
ftunivgoeteborg |
language |
English |
description |
To investigate microstructure in ice deformed under simple shear conditions experiments were performed with artificial polycrystalline ice and natural ice samples form Vatnajökull glacier in Iceland. A new deformation apparatus was tested and results from deformation were compared to literature to validate the method. Boundary conditions for deformation were varied. Experiments were performed at -5°C and -10°C and three strain rates were applied (2.5x10-7 1/s, 1.25x10-6 1/s, 2.5x10-6 1/s). It is shown that the natural samples, which contain only 2-3 grains, provide a close-up image on specific situation. This gives the opportunity to study them in detail. A special focus is set on the behaviour of grain boundaries during deformation. A preferred arrangement with at least one side of the boundary close to a prism face is seen. While in warm or slow deformations a tendency to favour boundaries with a combination of {1̅ 1̅ 22} and {101̅ 2} faces. The type of crystall face and their orientation towards deformation direction befor deformation has an major influence on the development during deformation. Brittle fractures were observed in the samples, which immediately filled with small new grains. This was only observed in samples deformed at -10°C but no dependency to strain rate was oberved. |
author2 |
University of Gothenburg/Department of Earth Sciences Göteborgs universitet/Institutionen för geovetenskaper |
format |
Text |
author |
Liebl, Carina |
spellingShingle |
Liebl, Carina Microstructural evolution of ice under simple shear deformation |
author_facet |
Liebl, Carina |
author_sort |
Liebl, Carina |
title |
Microstructural evolution of ice under simple shear deformation |
title_short |
Microstructural evolution of ice under simple shear deformation |
title_full |
Microstructural evolution of ice under simple shear deformation |
title_fullStr |
Microstructural evolution of ice under simple shear deformation |
title_full_unstemmed |
Microstructural evolution of ice under simple shear deformation |
title_sort |
microstructural evolution of ice under simple shear deformation |
publishDate |
2021 |
url |
http://hdl.handle.net/2077/67219 |
genre |
glacier Iceland Vatnajökull |
genre_facet |
glacier Iceland Vatnajökull |
op_relation |
B 1120 http://hdl.handle.net/2077/67219 |
_version_ |
1781060475926085632 |