Properties of grain boundary networks in the NEEM ice core
The microstructure along the entire NEEM ice core (North-West Greenland, 2537 m length) drilled in 2008-2011 has been analyzed based on a large data set of sublimation groove images. The sublimated surface of vertical section series (six consecutive 6 x 9 cm2 sections in steps of 20 m – in total abo...
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ftawi:oai:epic.awi.de:32809 2024-09-15T18:10:07+00:00 Properties of grain boundary networks in the NEEM ice core Binder, Tobias Weikusat, Ilka Freitag, Johannes Svensson, Anders Wagenbach, Dietmar Garbe, Christoph S. Kipfstuhl, Sepp 2013 application/pdf https://epic.awi.de/id/eprint/32809/ https://epic.awi.de/id/eprint/32809/1/EGU2013-4764.pdf https://hdl.handle.net/10013/epic.41354 https://hdl.handle.net/10013/epic.41354.d001 unknown https://epic.awi.de/id/eprint/32809/1/EGU2013-4764.pdf https://hdl.handle.net/10013/epic.41354.d001 Binder, T. , Weikusat, I. orcid:0000-0002-3023-6036 , Freitag, J. orcid:0000-0003-2654-9440 , Svensson, A. , Wagenbach, D. , Garbe, C. S. and Kipfstuhl, S. (2013) Properties of grain boundary networks in the NEEM ice core , EGU General Assembly 2013, Vienna, 7 April 2013 - 12 April 2013 . hdl:10013/epic.41354 EPIC3EGU General Assembly 2013, Vienna, 2013-04-07-2013-04-12 Conference notRev 2013 ftawi 2024-06-24T04:07:26Z The microstructure along the entire NEEM ice core (North-West Greenland, 2537 m length) drilled in 2008-2011 has been analyzed based on a large data set of sublimation groove images. The sublimated surface of vertical section series (six consecutive 6 x 9 cm2 sections in steps of 20 m – in total about 800 images) have been scanned by a Large Area Scanning Macroscope. In these cross-section images 10-15 micron wide grain boundary grooves and air bubbles appear dark, whereas the inside of grains appears gray (further developed by [S. Kipfstuhl et al., 2006, Journal of Glaciology, 52, 398-406]). A dedicated method of automatic image analysis has recently been developed to extract and parameterize the grain boundary networks of this set [T. Binder et al., 2013, Journal of Microscopy, in press]. In contrast to the microstructure obtained from thin sections between crossed polarizers in transmitted light, sublimation groove images in reflected light allow to include small grains (equivalent radius of 65 micron) in the size distribution. It has become possible to extract continuous curvature values of grain boundaries, an estimate of the lower bound of the stored strain energy and the dislocation density. In this contribution we give an overview on profiles of different calculated parameters related to deformation and recrystallization mechanisms. In older glaciological studies the value of the lower cut-off for grain sizes considered for calculation of a mean grain size has been arbitrary. We suggest to compare different definitions of the lower cut-off in the size. With respect to the important question which processes are dominating the grain size evolution in the late- to middle-Holocene, high sensitivity to the definition of this cut-off has been found [T. Binder et al., 2013, Materials Science Forum, 753, 481-484]. Between 250 m and 1000 m depth the curvature of grain boundaries steadily increases and grains become more irregularly shaped which correlates with increasing pressure of air bubbles. In the NEEM ice ... Conference Object Greenland ice core Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
The microstructure along the entire NEEM ice core (North-West Greenland, 2537 m length) drilled in 2008-2011 has been analyzed based on a large data set of sublimation groove images. The sublimated surface of vertical section series (six consecutive 6 x 9 cm2 sections in steps of 20 m – in total about 800 images) have been scanned by a Large Area Scanning Macroscope. In these cross-section images 10-15 micron wide grain boundary grooves and air bubbles appear dark, whereas the inside of grains appears gray (further developed by [S. Kipfstuhl et al., 2006, Journal of Glaciology, 52, 398-406]). A dedicated method of automatic image analysis has recently been developed to extract and parameterize the grain boundary networks of this set [T. Binder et al., 2013, Journal of Microscopy, in press]. In contrast to the microstructure obtained from thin sections between crossed polarizers in transmitted light, sublimation groove images in reflected light allow to include small grains (equivalent radius of 65 micron) in the size distribution. It has become possible to extract continuous curvature values of grain boundaries, an estimate of the lower bound of the stored strain energy and the dislocation density. In this contribution we give an overview on profiles of different calculated parameters related to deformation and recrystallization mechanisms. In older glaciological studies the value of the lower cut-off for grain sizes considered for calculation of a mean grain size has been arbitrary. We suggest to compare different definitions of the lower cut-off in the size. With respect to the important question which processes are dominating the grain size evolution in the late- to middle-Holocene, high sensitivity to the definition of this cut-off has been found [T. Binder et al., 2013, Materials Science Forum, 753, 481-484]. Between 250 m and 1000 m depth the curvature of grain boundaries steadily increases and grains become more irregularly shaped which correlates with increasing pressure of air bubbles. In the NEEM ice ... |
format |
Conference Object |
author |
Binder, Tobias Weikusat, Ilka Freitag, Johannes Svensson, Anders Wagenbach, Dietmar Garbe, Christoph S. Kipfstuhl, Sepp |
spellingShingle |
Binder, Tobias Weikusat, Ilka Freitag, Johannes Svensson, Anders Wagenbach, Dietmar Garbe, Christoph S. Kipfstuhl, Sepp Properties of grain boundary networks in the NEEM ice core |
author_facet |
Binder, Tobias Weikusat, Ilka Freitag, Johannes Svensson, Anders Wagenbach, Dietmar Garbe, Christoph S. Kipfstuhl, Sepp |
author_sort |
Binder, Tobias |
title |
Properties of grain boundary networks in the NEEM ice core |
title_short |
Properties of grain boundary networks in the NEEM ice core |
title_full |
Properties of grain boundary networks in the NEEM ice core |
title_fullStr |
Properties of grain boundary networks in the NEEM ice core |
title_full_unstemmed |
Properties of grain boundary networks in the NEEM ice core |
title_sort |
properties of grain boundary networks in the neem ice core |
publishDate |
2013 |
url |
https://epic.awi.de/id/eprint/32809/ https://epic.awi.de/id/eprint/32809/1/EGU2013-4764.pdf https://hdl.handle.net/10013/epic.41354 https://hdl.handle.net/10013/epic.41354.d001 |
genre |
Greenland ice core |
genre_facet |
Greenland ice core |
op_source |
EPIC3EGU General Assembly 2013, Vienna, 2013-04-07-2013-04-12 |
op_relation |
https://epic.awi.de/id/eprint/32809/1/EGU2013-4764.pdf https://hdl.handle.net/10013/epic.41354.d001 Binder, T. , Weikusat, I. orcid:0000-0002-3023-6036 , Freitag, J. orcid:0000-0003-2654-9440 , Svensson, A. , Wagenbach, D. , Garbe, C. S. and Kipfstuhl, S. (2013) Properties of grain boundary networks in the NEEM ice core , EGU General Assembly 2013, Vienna, 7 April 2013 - 12 April 2013 . hdl:10013/epic.41354 |
_version_ |
1810447719766949888 |