Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination
Sherpa Romeo green journal. Permission to archive final published version Bakaninbreen is a polythermal glacier in southern Spitsbergen, Svalbard, that last surged between 1985 and 1995. Seismic reflection data were acquired during early quiescence in spring 1998, just upstream of the surge front. T...
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ftunivlethb:oai:opus.uleth.ca:10133/5593 2023-05-15T15:11:21+02:00 Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination Smith, A. M. Murray, Tavi Davison, B. M. Clough, A. F. Woodward, J. Jiskoot, Hester 2002 application/pdf https://hdl.handle.net/10133/5593 en_US eng American Geophysical Union Arts and Science Department of Geography Natural Environmental Research Council (U.K.) University of Leeds Lancaster University Brunel University University of Calgary University of Lethbridge https://dx.doi.org/10.1029/2001JB000475 Smith, A. M., Murray, T., Davison, B. M., Clough, A. F., Woodward, J., & Jiskoot, H. (2002). Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination. Journal of Geophysical Research, 107(B8), 2152. doi:10.1029/2001JB000475 https://hdl.handle.net/10133/5593 Seismic GPR Glacier Surge Permafrost Arctic Article 2002 ftunivlethb 2021-06-27T07:19:29Z Sherpa Romeo green journal. Permission to archive final published version Bakaninbreen is a polythermal glacier in southern Spitsbergen, Svalbard, that last surged between 1985 and 1995. Seismic reflection data were acquired during early quiescence in spring 1998, just upstream of the surge front. The results were combined with complementary ground-penetrating radar data to investigate the glacial structure and basal conditions. We find no difference between the ice thickness values determined from the seismic and radar methods, suggesting that any layer of basal ice cannot be greater than 5 m thick. Interpretation of the amplitude of the seismic reflections indicates the presence of permafrost close to the glacier base. A thin layer of thawed deforming sediment separates the glacier from this underlying permafrost. In an area just upstream of the surge front the permafrost becomes discontinuous and may even be absent, the ice being underlain by 10–15 m of thawed sediments overlying deeper bedrock. Highpressure water is believed to have been required to maintain the propagation of the surge, and this area of thawed sediment is interpreted as a route for that water to escape from the basal system. When the surge front passed over this thawed bed, the escaping water reduced the pressure in the subglacial hydraulic system, initiating the termination of the surge. Surge termination was therefore primarily controlled by the presurge permafrost distribution beneath the glacier, rather than any feature of the surge itself. This termination mechanism is probably limited to surges in polythermal glaciers, but the techniques used may have wider glaciological applications. Yes Article in Journal/Newspaper Arctic glacier Ice permafrost Svalbard Spitsbergen University of Lethbridge Institutional Repository Arctic Bakaninbreen ENVELOPE(17.500,17.500,77.667,77.667) Romeo ENVELOPE(-59.927,-59.927,-62.376,-62.376) Svalbard |
institution |
Open Polar |
collection |
University of Lethbridge Institutional Repository |
op_collection_id |
ftunivlethb |
language |
English |
topic |
Seismic GPR Glacier Surge Permafrost Arctic |
spellingShingle |
Seismic GPR Glacier Surge Permafrost Arctic Smith, A. M. Murray, Tavi Davison, B. M. Clough, A. F. Woodward, J. Jiskoot, Hester Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination |
topic_facet |
Seismic GPR Glacier Surge Permafrost Arctic |
description |
Sherpa Romeo green journal. Permission to archive final published version Bakaninbreen is a polythermal glacier in southern Spitsbergen, Svalbard, that last surged between 1985 and 1995. Seismic reflection data were acquired during early quiescence in spring 1998, just upstream of the surge front. The results were combined with complementary ground-penetrating radar data to investigate the glacial structure and basal conditions. We find no difference between the ice thickness values determined from the seismic and radar methods, suggesting that any layer of basal ice cannot be greater than 5 m thick. Interpretation of the amplitude of the seismic reflections indicates the presence of permafrost close to the glacier base. A thin layer of thawed deforming sediment separates the glacier from this underlying permafrost. In an area just upstream of the surge front the permafrost becomes discontinuous and may even be absent, the ice being underlain by 10–15 m of thawed sediments overlying deeper bedrock. Highpressure water is believed to have been required to maintain the propagation of the surge, and this area of thawed sediment is interpreted as a route for that water to escape from the basal system. When the surge front passed over this thawed bed, the escaping water reduced the pressure in the subglacial hydraulic system, initiating the termination of the surge. Surge termination was therefore primarily controlled by the presurge permafrost distribution beneath the glacier, rather than any feature of the surge itself. This termination mechanism is probably limited to surges in polythermal glaciers, but the techniques used may have wider glaciological applications. Yes |
format |
Article in Journal/Newspaper |
author |
Smith, A. M. Murray, Tavi Davison, B. M. Clough, A. F. Woodward, J. Jiskoot, Hester |
author_facet |
Smith, A. M. Murray, Tavi Davison, B. M. Clough, A. F. Woodward, J. Jiskoot, Hester |
author_sort |
Smith, A. M. |
title |
Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination |
title_short |
Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination |
title_full |
Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination |
title_fullStr |
Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination |
title_full_unstemmed |
Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination |
title_sort |
late surge glacial conditions on bakaninbreen, svalbard, and implications for surge termination |
publisher |
American Geophysical Union |
publishDate |
2002 |
url |
https://hdl.handle.net/10133/5593 |
long_lat |
ENVELOPE(17.500,17.500,77.667,77.667) ENVELOPE(-59.927,-59.927,-62.376,-62.376) |
geographic |
Arctic Bakaninbreen Romeo Svalbard |
geographic_facet |
Arctic Bakaninbreen Romeo Svalbard |
genre |
Arctic glacier Ice permafrost Svalbard Spitsbergen |
genre_facet |
Arctic glacier Ice permafrost Svalbard Spitsbergen |
op_relation |
Smith, A. M., Murray, T., Davison, B. M., Clough, A. F., Woodward, J., & Jiskoot, H. (2002). Late surge glacial conditions on Bakaninbreen, Svalbard, and implications for surge termination. Journal of Geophysical Research, 107(B8), 2152. doi:10.1029/2001JB000475 https://hdl.handle.net/10133/5593 |
_version_ |
1766342217411067904 |