Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada)
Over the past decades, observations of buried glacier ice exposed in coastal bluffs and headwalls of retrogressive thaw slumps of the Arctic have indicated that considerable amounts of late Pleistocene glacier ice survived the deglaciation and are still preserved in permafrost. In exposures, relict...
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ftcopernicus:oai:publications.copernicus.org:tc69396 2023-05-15T14:58:09+02:00 Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada) Coulombe, Stephanie Fortier, Daniel Lacelle, Denis Kanevskiy, Mikhail Shur, Yuri 2019-01-11 application/pdf https://doi.org/10.5194/tc-13-97-2019 https://tc.copernicus.org/articles/13/97/2019/ eng eng doi:10.5194/tc-13-97-2019 https://tc.copernicus.org/articles/13/97/2019/ eISSN: 1994-0424 Text 2019 ftcopernicus https://doi.org/10.5194/tc-13-97-2019 2020-07-20T16:22:59Z Over the past decades, observations of buried glacier ice exposed in coastal bluffs and headwalls of retrogressive thaw slumps of the Arctic have indicated that considerable amounts of late Pleistocene glacier ice survived the deglaciation and are still preserved in permafrost. In exposures, relict glacier ice and intrasedimental ice often coexist and look alike but their genesis is strikingly different. This paper aims to present a detailed description and infer the origin of a massive ice body preserved in the permafrost of Bylot Island (Nunavut). The massive ice exposure and core samples were described according to the cryostratigraphic approach, combining the analysis of permafrost cryofacies and cryostructures, ice crystallography, stable O-H isotopes and cation contents. The ice was clear to whitish in appearance with large crystals (cm) and small gas inclusions (mm) at crystal intersections, similar to observations of englacial ice facies commonly found on contemporary glaciers and ice sheets. However, the δ 18 O composition ( <math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>-</mo><mn mathvariant="normal">34.0</mn><mo>±</mo><mn mathvariant="normal">0.4</mn></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="58pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="6c233401b15cd09b150017d0f113dbaa"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-13-97-2019-ie00001.svg" width="58pt" height="10pt" src="tc-13-97-2019-ie00001.png"/></svg:svg> ‰) of the massive ice was markedly lower than contemporary glacier ice and was consistent with the late Pleistocene age ice in the Barnes Ice Cap. This ice predates the aggradation of the surrounding permafrost and can be used as an archive to infer palaeo-environmental conditions at the study site. As most of the glaciated Arctic landscapes are still strongly determined by their glacial legacy, the melting of these large ice bodies could lead to extensive slope failures and settlement of the ground surface, with significant impact on permafrost geosystem landscape dynamics, terrestrial and aquatic ecosystems and infrastructure. Text Arctic Barnes Ice Cap Bylot Island glacier* Ice Ice cap Nunavut permafrost Copernicus Publications: E-Journals Arctic Barnes Ice Cap ENVELOPE(-73.498,-73.498,70.001,70.001) Bylot Island Canada Nunavut The Cryosphere 13 1 97 111 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Over the past decades, observations of buried glacier ice exposed in coastal bluffs and headwalls of retrogressive thaw slumps of the Arctic have indicated that considerable amounts of late Pleistocene glacier ice survived the deglaciation and are still preserved in permafrost. In exposures, relict glacier ice and intrasedimental ice often coexist and look alike but their genesis is strikingly different. This paper aims to present a detailed description and infer the origin of a massive ice body preserved in the permafrost of Bylot Island (Nunavut). The massive ice exposure and core samples were described according to the cryostratigraphic approach, combining the analysis of permafrost cryofacies and cryostructures, ice crystallography, stable O-H isotopes and cation contents. The ice was clear to whitish in appearance with large crystals (cm) and small gas inclusions (mm) at crystal intersections, similar to observations of englacial ice facies commonly found on contemporary glaciers and ice sheets. However, the δ 18 O composition ( <math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>-</mo><mn mathvariant="normal">34.0</mn><mo>±</mo><mn mathvariant="normal">0.4</mn></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="58pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="6c233401b15cd09b150017d0f113dbaa"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="tc-13-97-2019-ie00001.svg" width="58pt" height="10pt" src="tc-13-97-2019-ie00001.png"/></svg:svg> ‰) of the massive ice was markedly lower than contemporary glacier ice and was consistent with the late Pleistocene age ice in the Barnes Ice Cap. This ice predates the aggradation of the surrounding permafrost and can be used as an archive to infer palaeo-environmental conditions at the study site. As most of the glaciated Arctic landscapes are still strongly determined by their glacial legacy, the melting of these large ice bodies could lead to extensive slope failures and settlement of the ground surface, with significant impact on permafrost geosystem landscape dynamics, terrestrial and aquatic ecosystems and infrastructure. |
format |
Text |
author |
Coulombe, Stephanie Fortier, Daniel Lacelle, Denis Kanevskiy, Mikhail Shur, Yuri |
spellingShingle |
Coulombe, Stephanie Fortier, Daniel Lacelle, Denis Kanevskiy, Mikhail Shur, Yuri Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada) |
author_facet |
Coulombe, Stephanie Fortier, Daniel Lacelle, Denis Kanevskiy, Mikhail Shur, Yuri |
author_sort |
Coulombe, Stephanie |
title |
Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada) |
title_short |
Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada) |
title_full |
Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada) |
title_fullStr |
Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada) |
title_full_unstemmed |
Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada) |
title_sort |
origin, burial and preservation of late pleistocene-age glacier ice in arctic permafrost (bylot island, nu, canada) |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-13-97-2019 https://tc.copernicus.org/articles/13/97/2019/ |
long_lat |
ENVELOPE(-73.498,-73.498,70.001,70.001) |
geographic |
Arctic Barnes Ice Cap Bylot Island Canada Nunavut |
geographic_facet |
Arctic Barnes Ice Cap Bylot Island Canada Nunavut |
genre |
Arctic Barnes Ice Cap Bylot Island glacier* Ice Ice cap Nunavut permafrost |
genre_facet |
Arctic Barnes Ice Cap Bylot Island glacier* Ice Ice cap Nunavut permafrost |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-13-97-2019 https://tc.copernicus.org/articles/13/97/2019/ |
op_doi |
https://doi.org/10.5194/tc-13-97-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
1 |
container_start_page |
97 |
op_container_end_page |
111 |
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1766330246635716608 |