Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration
SUMMARY In this contribution we model flow‐induced anisotropy of polar ice in order to gain a better understanding for the underlying microstructure and its influence on the deformation process. In particular, a continuum‐mechanical, anisotropic flow model that is based on an anisotropic flow enhanc...
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crwiley:10.1002/nag.1034 2024-06-02T07:57:08+00:00 Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration Bargmann, Swantje Seddik, Hakime Greve, Ralf 2011 http://dx.doi.org/10.1002/nag.1034 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fnag.1034 https://onlinelibrary.wiley.com/doi/pdf/10.1002/nag.1034 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor International Journal for Numerical and Analytical Methods in Geomechanics volume 36, issue 7, page 892-917 ISSN 0363-9061 1096-9853 journal-article 2011 crwiley https://doi.org/10.1002/nag.1034 2024-05-03T10:40:35Z SUMMARY In this contribution we model flow‐induced anisotropy of polar ice in order to gain a better understanding for the underlying microstructure and its influence on the deformation process. In particular, a continuum‐mechanical, anisotropic flow model that is based on an anisotropic flow enhancement factor (CAFFE model) is applied. The polycrystalline ice is regarded as a mixture whose grains are characterized by their orientation. The approach is based on two distinct scales: the underlying microstructure influences the macroscopic material behavior and is taken into account phenomenologically. To achieve this, the orientation mass density is introduced as a mesoscopic field, i.e. it depends on a mesoscopic variable (the orientation) in addition to position and time. The classical flow law of Glen is extended by a scalar, but anisotropic enhancement factor. Four different effects (local rigid body rotation, grain rotation, rotation recrystallization, grain boundary migration) influencing the evolution of the grain orientations are taken into account. All modeling parameters are either measurable in or derivable from field observations or laboratory experiments. A finite volume method is chosen for the discretization procedure. Numerical results simulating the ice flow at the site of the EPICA ice core in Dronning Maud Land (referred to as EDML), Antarctica, are presented. They go beyond earlier results by Seddikit et al. ( J. Glaciol. 2008; 54 (187):631–642) in which only local rigid body rotation and grain rotation were accounted for. By comparing simulated and observed fabrics, we come up with reference values for the parameters in the constitutive equations for rotation recrystallization and grain boundary migration. Down to 2045 m depth, good agreement can be achieved; however, further down the observed fabric cannot be reproduced well due to numerical issues. Additionally, we study the influence of the two superposed deformation regimes of vertical compression and simple shear separately and ... Article in Journal/Newspaper Antarc* Antarctica Dronning Maud Land EPICA ice core Wiley Online Library Dronning Maud Land International Journal for Numerical and Analytical Methods in Geomechanics 36 7 892 917 |
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Open Polar |
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Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
SUMMARY In this contribution we model flow‐induced anisotropy of polar ice in order to gain a better understanding for the underlying microstructure and its influence on the deformation process. In particular, a continuum‐mechanical, anisotropic flow model that is based on an anisotropic flow enhancement factor (CAFFE model) is applied. The polycrystalline ice is regarded as a mixture whose grains are characterized by their orientation. The approach is based on two distinct scales: the underlying microstructure influences the macroscopic material behavior and is taken into account phenomenologically. To achieve this, the orientation mass density is introduced as a mesoscopic field, i.e. it depends on a mesoscopic variable (the orientation) in addition to position and time. The classical flow law of Glen is extended by a scalar, but anisotropic enhancement factor. Four different effects (local rigid body rotation, grain rotation, rotation recrystallization, grain boundary migration) influencing the evolution of the grain orientations are taken into account. All modeling parameters are either measurable in or derivable from field observations or laboratory experiments. A finite volume method is chosen for the discretization procedure. Numerical results simulating the ice flow at the site of the EPICA ice core in Dronning Maud Land (referred to as EDML), Antarctica, are presented. They go beyond earlier results by Seddikit et al. ( J. Glaciol. 2008; 54 (187):631–642) in which only local rigid body rotation and grain rotation were accounted for. By comparing simulated and observed fabrics, we come up with reference values for the parameters in the constitutive equations for rotation recrystallization and grain boundary migration. Down to 2045 m depth, good agreement can be achieved; however, further down the observed fabric cannot be reproduced well due to numerical issues. Additionally, we study the influence of the two superposed deformation regimes of vertical compression and simple shear separately and ... |
format |
Article in Journal/Newspaper |
author |
Bargmann, Swantje Seddik, Hakime Greve, Ralf |
spellingShingle |
Bargmann, Swantje Seddik, Hakime Greve, Ralf Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration |
author_facet |
Bargmann, Swantje Seddik, Hakime Greve, Ralf |
author_sort |
Bargmann, Swantje |
title |
Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration |
title_short |
Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration |
title_full |
Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration |
title_fullStr |
Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration |
title_full_unstemmed |
Computational modeling of flow‐induced anisotropy of polar ice for the EDML deep drilling site, Antarctica: The effect of rotation recrystallization and grain boundary migration |
title_sort |
computational modeling of flow‐induced anisotropy of polar ice for the edml deep drilling site, antarctica: the effect of rotation recrystallization and grain boundary migration |
publisher |
Wiley |
publishDate |
2011 |
url |
http://dx.doi.org/10.1002/nag.1034 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fnag.1034 https://onlinelibrary.wiley.com/doi/pdf/10.1002/nag.1034 |
geographic |
Dronning Maud Land |
geographic_facet |
Dronning Maud Land |
genre |
Antarc* Antarctica Dronning Maud Land EPICA ice core |
genre_facet |
Antarc* Antarctica Dronning Maud Land EPICA ice core |
op_source |
International Journal for Numerical and Analytical Methods in Geomechanics volume 36, issue 7, page 892-917 ISSN 0363-9061 1096-9853 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/nag.1034 |
container_title |
International Journal for Numerical and Analytical Methods in Geomechanics |
container_volume |
36 |
container_issue |
7 |
container_start_page |
892 |
op_container_end_page |
917 |
_version_ |
1800738950258622464 |