Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier
Abstract Drumlins form at the ice/bed interface through subglacial processes that are not directly observable. The internal stratigraphy of drumlins provides insight into how they developed and associated subglacial processes, but traditional stratigraphic logging techniques are limited to natural e...
Published in: | Journal of Glaciology |
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Language: | English |
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Cambridge University Press (CUP)
2020
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Online Access: | http://dx.doi.org/10.1017/jog.2020.50 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020000507 |
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crcambridgeupr:10.1017/jog.2020.50 2024-09-15T18:07:48+00:00 Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier Woodard, Jacob B. Zoet, Lucas K. Benediktsson, Ívar Ö. Iverson, Neal R. Finlayson, Andrew 2020 http://dx.doi.org/10.1017/jog.2020.50 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020000507 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 66, issue 259, page 822-830 ISSN 0022-1430 1727-5652 journal-article 2020 crcambridgeupr https://doi.org/10.1017/jog.2020.50 2024-07-24T04:02:47Z Abstract Drumlins form at the ice/bed interface through subglacial processes that are not directly observable. The internal stratigraphy of drumlins provides insight into how they developed and associated subglacial processes, but traditional stratigraphic logging techniques are limited to natural exposures and excavations. Using ground-penetrating radar, we imaged the internal stratigraphy of seven drumlins from a recently exposed drumlin field in the forefield of Múlajökull, Iceland. Data were collected with 100 and 200 MHz antennas with maximum resolvable depths of 8 and 4 m, respectively. Longitudinal echograms contained coherent down-ice dipping reflectors over the lengths of the drumlins. Near the drumlin heads (i.e., stoss sides), down-glacier dipping beds lie at high angles to the surface, whereas on the lee sides, the down-glacier dipping beds lie at low angles, or conform, to drumlin surfaces. Transverse echograms exhibited unconformities along the flanks of drumlin heads and conformable bedding across the lee side widths of the drumlins. These observations were ground-truthed with stratigraphic logs from a subset of drumlins and good agreement was found. The stratigraphic patterns support previous conclusions that drumlins at Múlajökull formed on a deformable bed through both depositional and erosional processes which may alternate between its surge and quiescent phases. Article in Journal/Newspaper glacier Iceland Journal of Glaciology Cambridge University Press Journal of Glaciology 66 259 822 830 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract Drumlins form at the ice/bed interface through subglacial processes that are not directly observable. The internal stratigraphy of drumlins provides insight into how they developed and associated subglacial processes, but traditional stratigraphic logging techniques are limited to natural exposures and excavations. Using ground-penetrating radar, we imaged the internal stratigraphy of seven drumlins from a recently exposed drumlin field in the forefield of Múlajökull, Iceland. Data were collected with 100 and 200 MHz antennas with maximum resolvable depths of 8 and 4 m, respectively. Longitudinal echograms contained coherent down-ice dipping reflectors over the lengths of the drumlins. Near the drumlin heads (i.e., stoss sides), down-glacier dipping beds lie at high angles to the surface, whereas on the lee sides, the down-glacier dipping beds lie at low angles, or conform, to drumlin surfaces. Transverse echograms exhibited unconformities along the flanks of drumlin heads and conformable bedding across the lee side widths of the drumlins. These observations were ground-truthed with stratigraphic logs from a subset of drumlins and good agreement was found. The stratigraphic patterns support previous conclusions that drumlins at Múlajökull formed on a deformable bed through both depositional and erosional processes which may alternate between its surge and quiescent phases. |
format |
Article in Journal/Newspaper |
author |
Woodard, Jacob B. Zoet, Lucas K. Benediktsson, Ívar Ö. Iverson, Neal R. Finlayson, Andrew |
spellingShingle |
Woodard, Jacob B. Zoet, Lucas K. Benediktsson, Ívar Ö. Iverson, Neal R. Finlayson, Andrew Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier |
author_facet |
Woodard, Jacob B. Zoet, Lucas K. Benediktsson, Ívar Ö. Iverson, Neal R. Finlayson, Andrew |
author_sort |
Woodard, Jacob B. |
title |
Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier |
title_short |
Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier |
title_full |
Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier |
title_fullStr |
Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier |
title_full_unstemmed |
Insights into drumlin development from ground-penetrating radar at Múlajökull, Iceland, a surge-type glacier |
title_sort |
insights into drumlin development from ground-penetrating radar at múlajökull, iceland, a surge-type glacier |
publisher |
Cambridge University Press (CUP) |
publishDate |
2020 |
url |
http://dx.doi.org/10.1017/jog.2020.50 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020000507 |
genre |
glacier Iceland Journal of Glaciology |
genre_facet |
glacier Iceland Journal of Glaciology |
op_source |
Journal of Glaciology volume 66, issue 259, page 822-830 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2020.50 |
container_title |
Journal of Glaciology |
container_volume |
66 |
container_issue |
259 |
container_start_page |
822 |
op_container_end_page |
830 |
_version_ |
1810445174181986304 |