The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum
The hydraulic behaviour of meltwater during subglacial basaltic eruptions in temperate ice is of paramount importance in understanding the eruptive processes, lithofacies and architecture of the edifices formed. Hydraulics also determines the timing, location and volume of meltwater discharge, which...
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ftnerc:oai:nora.nerc.ac.uk:124 2024-06-09T07:39:48+00:00 The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum Smellie, J.L. 2006 http://nora.nerc.ac.uk/id/eprint/124/ https://doi.org/10.1016/j.earscirev.2005.09.004 unknown Elsevier Smellie, J.L. 2006 The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum. Earth-Science Reviews, 74 (3-4). 241-268. https://doi.org/10.1016/j.earscirev.2005.09.004 <https://doi.org/10.1016/j.earscirev.2005.09.004> Earth Sciences Publication - Article PeerReviewed 2006 ftnerc https://doi.org/10.1016/j.earscirev.2005.09.004 2024-05-15T08:39:04Z The hydraulic behaviour of meltwater during subglacial basaltic eruptions in temperate ice is of paramount importance in understanding the eruptive processes, lithofacies and architecture of the edifices formed. Hydraulics also determines the timing, location and volume of meltwater discharge, which may be sudden and catastrophic and via subglacial and/or supraglacial routes. Increasing our knowledge of meltwater hydraulics is therefore important for understanding, predicting and mitigating the impact of meltwater release on vulnerable human communities. New observations about eruption-related meltwater hydraulics are presented for well-exposed glaciovolcanic lava-fed deltas on James Ross Island, Antarctica, and accounts of historical eruptions are also re-examined to identify the major meltwater discharge routes. The study provides the first conceptual model for how meltwater escapes supraglacially. In the absence of a crevassed layer (which will dominate any meltwater flow), overflowing may be initiated by enhanced rates of seepage, despite the intrinsically low hydraulic conductivities of snow and firn. Once overflowing is established, the rate of spillway incision is a likely overriding control on the evolution of the system and whether the discharge is unstable (fast) or stable (slower). The James Ross Island sequences demonstrate that meltwater discharge is highly dynamic and may have involved both subglacial and supraglacial escape. Subglacial discharge probably occurs throughout basaltic tuya eruptions but some periods may be dominated by concurrent overflowing. It is still unclear if overflowing systems are sufficiently stable to enable the growth of laterally extensive glaciovolcanic lava-fed deltas. Article in Journal/Newspaper Antarc* Antarctica James Ross Island Ross Island Natural Environment Research Council: NERC Open Research Archive Ross Island Earth-Science Reviews 74 3-4 241 268 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Smellie, J.L. The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum |
topic_facet |
Earth Sciences |
description |
The hydraulic behaviour of meltwater during subglacial basaltic eruptions in temperate ice is of paramount importance in understanding the eruptive processes, lithofacies and architecture of the edifices formed. Hydraulics also determines the timing, location and volume of meltwater discharge, which may be sudden and catastrophic and via subglacial and/or supraglacial routes. Increasing our knowledge of meltwater hydraulics is therefore important for understanding, predicting and mitigating the impact of meltwater release on vulnerable human communities. New observations about eruption-related meltwater hydraulics are presented for well-exposed glaciovolcanic lava-fed deltas on James Ross Island, Antarctica, and accounts of historical eruptions are also re-examined to identify the major meltwater discharge routes. The study provides the first conceptual model for how meltwater escapes supraglacially. In the absence of a crevassed layer (which will dominate any meltwater flow), overflowing may be initiated by enhanced rates of seepage, despite the intrinsically low hydraulic conductivities of snow and firn. Once overflowing is established, the rate of spillway incision is a likely overriding control on the evolution of the system and whether the discharge is unstable (fast) or stable (slower). The James Ross Island sequences demonstrate that meltwater discharge is highly dynamic and may have involved both subglacial and supraglacial escape. Subglacial discharge probably occurs throughout basaltic tuya eruptions but some periods may be dominated by concurrent overflowing. It is still unclear if overflowing systems are sufficiently stable to enable the growth of laterally extensive glaciovolcanic lava-fed deltas. |
format |
Article in Journal/Newspaper |
author |
Smellie, J.L. |
author_facet |
Smellie, J.L. |
author_sort |
Smellie, J.L. |
title |
The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum |
title_short |
The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum |
title_full |
The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum |
title_fullStr |
The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum |
title_full_unstemmed |
The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum |
title_sort |
relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum |
publisher |
Elsevier |
publishDate |
2006 |
url |
http://nora.nerc.ac.uk/id/eprint/124/ https://doi.org/10.1016/j.earscirev.2005.09.004 |
geographic |
Ross Island |
geographic_facet |
Ross Island |
genre |
Antarc* Antarctica James Ross Island Ross Island |
genre_facet |
Antarc* Antarctica James Ross Island Ross Island |
op_relation |
Smellie, J.L. 2006 The relative importance of supraglacial versus subglacial meltwater escape in basaltic subglacial tuya eruptions: an important unresolved conundrum. Earth-Science Reviews, 74 (3-4). 241-268. https://doi.org/10.1016/j.earscirev.2005.09.004 <https://doi.org/10.1016/j.earscirev.2005.09.004> |
op_doi |
https://doi.org/10.1016/j.earscirev.2005.09.004 |
container_title |
Earth-Science Reviews |
container_volume |
74 |
container_issue |
3-4 |
container_start_page |
241 |
op_container_end_page |
268 |
_version_ |
1801382104326471680 |