Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland
Subglacial hydrology modulates basal motion but remains poorly constrained, particularly for soft-bedded Greenlandic outlet glaciers. Here, we report detailed measurements of the response of subglacial water pressure to the connection and drainage of adjacent water-filled boreholes drilled through k...
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Cambridge University Press
2022
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ftdoajarticles:oai:doaj.org/article:b42d1c1436d1446fa38ba96388fa36a5 2023-05-15T16:21:26+02:00 Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland Samuel H. Doyle Bryn Hubbard Poul Christoffersen Robert Law Duncan R. Hewitt Jerome A. Neufeld Charlotte M. Schoonman Thomas R. Chudley Marion Bougamont 2022-08-01T00:00:00Z https://doi.org/10.1017/jog.2021.121 https://doaj.org/article/b42d1c1436d1446fa38ba96388fa36a5 EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143021001210/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2021.121 0022-1430 1727-5652 https://doaj.org/article/b42d1c1436d1446fa38ba96388fa36a5 Journal of Glaciology, Vol 68, Pp 665-684 (2022) Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2022 ftdoajarticles https://doi.org/10.1017/jog.2021.121 2023-03-12T01:30:54Z Subglacial hydrology modulates basal motion but remains poorly constrained, particularly for soft-bedded Greenlandic outlet glaciers. Here, we report detailed measurements of the response of subglacial water pressure to the connection and drainage of adjacent water-filled boreholes drilled through kilometre-thick ice on Sermeq Kujalleq (Store Glacier). These measurements provide evidence for gap opening at the ice-sediment interface, Darcian flow through the sediment layer, and the forcing of water pressure in hydraulically-isolated cavities by stress transfer. We observed a small pressure drop followed by a large pressure rise in response to the connection of an adjacent borehole, consistent with the propagation of a flexural wave within the ice and underlying deformable sediment. We interpret the delayed pressure rise as evidence of no pre-existing conduit and the progressive decrease in hydraulic transmissivity as the closure of a narrow (< 1.5 mm) gap opened at the ice-sediment interface, and a reversion to Darcian flow through the sediment layer with a hydraulic conductivity of ≤ 10−6 m s−1. We suggest that gap opening at the ice-sediment interface deserves further attention as it will occur naturally in response to the rapid pressurisation of water at the bed. Article in Journal/Newspaper glacier Greenland greenlandic Journal of Glaciology Kujalleq Sermeq Kujalleq Directory of Open Access Journals: DOAJ Articles Greenland Kujalleq ENVELOPE(-46.037,-46.037,60.719,60.719) Journal of Glaciology 68 270 665 684 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
Environmental sciences GE1-350 Meteorology. Climatology QC851-999 Samuel H. Doyle Bryn Hubbard Poul Christoffersen Robert Law Duncan R. Hewitt Jerome A. Neufeld Charlotte M. Schoonman Thomas R. Chudley Marion Bougamont Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland |
topic_facet |
Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
Subglacial hydrology modulates basal motion but remains poorly constrained, particularly for soft-bedded Greenlandic outlet glaciers. Here, we report detailed measurements of the response of subglacial water pressure to the connection and drainage of adjacent water-filled boreholes drilled through kilometre-thick ice on Sermeq Kujalleq (Store Glacier). These measurements provide evidence for gap opening at the ice-sediment interface, Darcian flow through the sediment layer, and the forcing of water pressure in hydraulically-isolated cavities by stress transfer. We observed a small pressure drop followed by a large pressure rise in response to the connection of an adjacent borehole, consistent with the propagation of a flexural wave within the ice and underlying deformable sediment. We interpret the delayed pressure rise as evidence of no pre-existing conduit and the progressive decrease in hydraulic transmissivity as the closure of a narrow (< 1.5 mm) gap opened at the ice-sediment interface, and a reversion to Darcian flow through the sediment layer with a hydraulic conductivity of ≤ 10−6 m s−1. We suggest that gap opening at the ice-sediment interface deserves further attention as it will occur naturally in response to the rapid pressurisation of water at the bed. |
format |
Article in Journal/Newspaper |
author |
Samuel H. Doyle Bryn Hubbard Poul Christoffersen Robert Law Duncan R. Hewitt Jerome A. Neufeld Charlotte M. Schoonman Thomas R. Chudley Marion Bougamont |
author_facet |
Samuel H. Doyle Bryn Hubbard Poul Christoffersen Robert Law Duncan R. Hewitt Jerome A. Neufeld Charlotte M. Schoonman Thomas R. Chudley Marion Bougamont |
author_sort |
Samuel H. Doyle |
title |
Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland |
title_short |
Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland |
title_full |
Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland |
title_fullStr |
Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland |
title_full_unstemmed |
Water flow through sediments and at the ice-sediment interface beneath Sermeq Kujalleq (Store Glacier), Greenland |
title_sort |
water flow through sediments and at the ice-sediment interface beneath sermeq kujalleq (store glacier), greenland |
publisher |
Cambridge University Press |
publishDate |
2022 |
url |
https://doi.org/10.1017/jog.2021.121 https://doaj.org/article/b42d1c1436d1446fa38ba96388fa36a5 |
long_lat |
ENVELOPE(-46.037,-46.037,60.719,60.719) |
geographic |
Greenland Kujalleq |
geographic_facet |
Greenland Kujalleq |
genre |
glacier Greenland greenlandic Journal of Glaciology Kujalleq Sermeq Kujalleq |
genre_facet |
glacier Greenland greenlandic Journal of Glaciology Kujalleq Sermeq Kujalleq |
op_source |
Journal of Glaciology, Vol 68, Pp 665-684 (2022) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143021001210/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2021.121 0022-1430 1727-5652 https://doaj.org/article/b42d1c1436d1446fa38ba96388fa36a5 |
op_doi |
https://doi.org/10.1017/jog.2021.121 |
container_title |
Journal of Glaciology |
container_volume |
68 |
container_issue |
270 |
container_start_page |
665 |
op_container_end_page |
684 |
_version_ |
1766009431146889216 |