Diffuse debris entrainment in glacier, lab and model environments
Small quantities of liquid water lining triple junctions in polycrystalline glacier ice form connected vein networks that enable material exchange with underlying basal environments. Diffuse debris concentrations commonly observed in ice marginal regions might be attributed to this mechanism. Follow...
Published in: | Annals of Glaciology |
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Cambridge University Press
2023
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Online Access: | https://doi.org/10.1017/aog.2023.31 https://doaj.org/article/48036921f0524bf3891b1b31f670e030 |
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ftdoajarticles:oai:doaj.org/article:48036921f0524bf3891b1b31f670e030 2024-09-15T17:39:56+00:00 Diffuse debris entrainment in glacier, lab and model environments Alan W. Rempel Dougal D. Hansen Luke K. Zoet Colin R. Meyer 2023-04-01T00:00:00Z https://doi.org/10.1017/aog.2023.31 https://doaj.org/article/48036921f0524bf3891b1b31f670e030 EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0260305523000319/type/journal_article https://doaj.org/toc/0260-3055 https://doaj.org/toc/1727-5644 doi:10.1017/aog.2023.31 0260-3055 1727-5644 https://doaj.org/article/48036921f0524bf3891b1b31f670e030 Annals of Glaciology, Vol 64, Pp 13-25 (2023) Basal ice ice physics melt - basal subglacial processes subglacial precipitates and ice regelation Meteorology. Climatology QC851-999 article 2023 ftdoajarticles https://doi.org/10.1017/aog.2023.31 2024-08-05T17:49:57Z Small quantities of liquid water lining triple junctions in polycrystalline glacier ice form connected vein networks that enable material exchange with underlying basal environments. Diffuse debris concentrations commonly observed in ice marginal regions might be attributed to this mechanism. Following recent cryogenic ring-shear experiments, we observed emplacement along grain boundaries of loess particles several tens of microns in size. Here, we describe an idealized model of vein liquid flow to elucidate conditions favoring such particle transport. Gradients in liquid potential drive flow toward colder temperatures and lower solute concentrations, while deviations of the ice stress state from hydrostatic balance produce additional suction toward anomalously low ice pressures. Our model predicts particle entrainment following both modest warming along the basal interface resulting from anticipated natural changes in effective stress, and the interior relaxation of temperature and solute concentration imposed by our experimental protocols. Comparisons with experimental observations are encouraging, but suggest that liquid flow rates are somewhat higher and/or more effective at dragging larger particles than predicted by our idealized model with nominal parameter choices. Diffuse debris entrainment extending several meters above the glacier bed likely requires a more sophisticated treatment that incorporates effects of ice deformation or other processes. Article in Journal/Newspaper Annals of Glaciology Directory of Open Access Journals: DOAJ Articles Annals of Glaciology 1 13 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Basal ice ice physics melt - basal subglacial processes subglacial precipitates and ice regelation Meteorology. Climatology QC851-999 |
spellingShingle |
Basal ice ice physics melt - basal subglacial processes subglacial precipitates and ice regelation Meteorology. Climatology QC851-999 Alan W. Rempel Dougal D. Hansen Luke K. Zoet Colin R. Meyer Diffuse debris entrainment in glacier, lab and model environments |
topic_facet |
Basal ice ice physics melt - basal subglacial processes subglacial precipitates and ice regelation Meteorology. Climatology QC851-999 |
description |
Small quantities of liquid water lining triple junctions in polycrystalline glacier ice form connected vein networks that enable material exchange with underlying basal environments. Diffuse debris concentrations commonly observed in ice marginal regions might be attributed to this mechanism. Following recent cryogenic ring-shear experiments, we observed emplacement along grain boundaries of loess particles several tens of microns in size. Here, we describe an idealized model of vein liquid flow to elucidate conditions favoring such particle transport. Gradients in liquid potential drive flow toward colder temperatures and lower solute concentrations, while deviations of the ice stress state from hydrostatic balance produce additional suction toward anomalously low ice pressures. Our model predicts particle entrainment following both modest warming along the basal interface resulting from anticipated natural changes in effective stress, and the interior relaxation of temperature and solute concentration imposed by our experimental protocols. Comparisons with experimental observations are encouraging, but suggest that liquid flow rates are somewhat higher and/or more effective at dragging larger particles than predicted by our idealized model with nominal parameter choices. Diffuse debris entrainment extending several meters above the glacier bed likely requires a more sophisticated treatment that incorporates effects of ice deformation or other processes. |
format |
Article in Journal/Newspaper |
author |
Alan W. Rempel Dougal D. Hansen Luke K. Zoet Colin R. Meyer |
author_facet |
Alan W. Rempel Dougal D. Hansen Luke K. Zoet Colin R. Meyer |
author_sort |
Alan W. Rempel |
title |
Diffuse debris entrainment in glacier, lab and model environments |
title_short |
Diffuse debris entrainment in glacier, lab and model environments |
title_full |
Diffuse debris entrainment in glacier, lab and model environments |
title_fullStr |
Diffuse debris entrainment in glacier, lab and model environments |
title_full_unstemmed |
Diffuse debris entrainment in glacier, lab and model environments |
title_sort |
diffuse debris entrainment in glacier, lab and model environments |
publisher |
Cambridge University Press |
publishDate |
2023 |
url |
https://doi.org/10.1017/aog.2023.31 https://doaj.org/article/48036921f0524bf3891b1b31f670e030 |
genre |
Annals of Glaciology |
genre_facet |
Annals of Glaciology |
op_source |
Annals of Glaciology, Vol 64, Pp 13-25 (2023) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0260305523000319/type/journal_article https://doaj.org/toc/0260-3055 https://doaj.org/toc/1727-5644 doi:10.1017/aog.2023.31 0260-3055 1727-5644 https://doaj.org/article/48036921f0524bf3891b1b31f670e030 |
op_doi |
https://doi.org/10.1017/aog.2023.31 |
container_title |
Annals of Glaciology |
container_start_page |
1 |
op_container_end_page |
13 |
_version_ |
1810483479301849088 |