Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada
The role of shore ice and freeze-thaw processes in intertidal sediments was studied along the inner shoreline of Manitounuk Strait through a series of drillings through the ice foot and numerous observations at all seasons. Mechanical processes such as drift-ice scouring and clast transport play onl...
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Online Access: | https://hal.science/hal-04314576 https://doi.org/10.1139/e98-055 |
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ftinsu:oai:HAL:hal-04314576v1 2023-12-31T10:23:28+01:00 Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada Allard, Michel Michaud, Yves Ruz, Marie-Hélène Héquette, Arnaud Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG) Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Nord ) Université du Littoral Côte d'Opale (ULCO) 1998-09-01 https://hal.science/hal-04314576 https://doi.org/10.1139/e98-055 en eng HAL CCSD National Research Council Canada info:eu-repo/semantics/altIdentifier/doi/10.1139/e98-055 hal-04314576 https://hal.science/hal-04314576 doi:10.1139/e98-055 ISSN: 0008-4077 EISSN: 1480-3313 Canadian journal of earth sciences https://hal.science/hal-04314576 Canadian journal of earth sciences, 1998, 35 (9), pp.965-979. ⟨10.1139/e98-055⟩ [SDE]Environmental Sciences info:eu-repo/semantics/article Journal articles 1998 ftinsu https://doi.org/10.1139/e98-055 2023-12-06T17:23:04Z The role of shore ice and freeze-thaw processes in intertidal sediments was studied along the inner shoreline of Manitounuk Strait through a series of drillings through the ice foot and numerous observations at all seasons. Mechanical processes such as drift-ice scouring and clast transport play only a minimal part in the observed changes. The thermal behaviour of the ice foot and the control it exerts on surface and groundwater flow throughout winter are the dominant factors of the shoreline dynamics. As the ice foot freezes to the surface of the tidal flat, a freezing front penetrates to depths of 3 m in the underlying sediments, which consist of postglacial Tyrrell Sea clays. This induces the formation of segregation ice which destroys the structure of the clays and leads to their thaw liquefaction in early summer. As this deep penetration of frost beneath the ice foot also impedes winter groundwater and surface-water flow, forced seepage and springs form icings (naleds), frost blisters, and lens-shaped bodies of intrusive ground ice at the upper margin of the tidal zone. The melting of all this ground ice induces settlement, microcliff collapse, and mud flows. The Manitounuk tidal zone, rather than being a typical tidal flat, is an erosional platform that is cut in soft Quaternary sediments and is being graded to tidal regime. Freeze-thaw processes controlled by the presence and thermal behaviour of the ice foot are the principal agents of platform destruction while waves and tidal currents are the transport agents that remove the sediments from the tidal zone. Platform erosion is presently the main source for sediment deposition in the shallow waters of Manitounuk Strait. Such a series of coastal periglacial processes may play an important role in other subarctic coastal settings. They also play an important ecological role, as they prevent the colonization of the coastal zone by mollusks and restrict the extent of coastal marshes. Article in Journal/Newspaper Subarctic Institut national des sciences de l'Univers: HAL-INSU Canadian Journal of Earth Sciences 35 9 965 979 |
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Open Polar |
collection |
Institut national des sciences de l'Univers: HAL-INSU |
op_collection_id |
ftinsu |
language |
English |
topic |
[SDE]Environmental Sciences |
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[SDE]Environmental Sciences Allard, Michel Michaud, Yves Ruz, Marie-Hélène Héquette, Arnaud Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada |
topic_facet |
[SDE]Environmental Sciences |
description |
The role of shore ice and freeze-thaw processes in intertidal sediments was studied along the inner shoreline of Manitounuk Strait through a series of drillings through the ice foot and numerous observations at all seasons. Mechanical processes such as drift-ice scouring and clast transport play only a minimal part in the observed changes. The thermal behaviour of the ice foot and the control it exerts on surface and groundwater flow throughout winter are the dominant factors of the shoreline dynamics. As the ice foot freezes to the surface of the tidal flat, a freezing front penetrates to depths of 3 m in the underlying sediments, which consist of postglacial Tyrrell Sea clays. This induces the formation of segregation ice which destroys the structure of the clays and leads to their thaw liquefaction in early summer. As this deep penetration of frost beneath the ice foot also impedes winter groundwater and surface-water flow, forced seepage and springs form icings (naleds), frost blisters, and lens-shaped bodies of intrusive ground ice at the upper margin of the tidal zone. The melting of all this ground ice induces settlement, microcliff collapse, and mud flows. The Manitounuk tidal zone, rather than being a typical tidal flat, is an erosional platform that is cut in soft Quaternary sediments and is being graded to tidal regime. Freeze-thaw processes controlled by the presence and thermal behaviour of the ice foot are the principal agents of platform destruction while waves and tidal currents are the transport agents that remove the sediments from the tidal zone. Platform erosion is presently the main source for sediment deposition in the shallow waters of Manitounuk Strait. Such a series of coastal periglacial processes may play an important role in other subarctic coastal settings. They also play an important ecological role, as they prevent the colonization of the coastal zone by mollusks and restrict the extent of coastal marshes. |
author2 |
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG) Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Nord ) Université du Littoral Côte d'Opale (ULCO) |
format |
Article in Journal/Newspaper |
author |
Allard, Michel Michaud, Yves Ruz, Marie-Hélène Héquette, Arnaud |
author_facet |
Allard, Michel Michaud, Yves Ruz, Marie-Hélène Héquette, Arnaud |
author_sort |
Allard, Michel |
title |
Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada |
title_short |
Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada |
title_full |
Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada |
title_fullStr |
Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada |
title_full_unstemmed |
Ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, Manitounuk Strait, northern Quebec, Canada |
title_sort |
ice foot, freeze-thaw of sediments, and platform erosion in a subarctic microtidal environment, manitounuk strait, northern quebec, canada |
publisher |
HAL CCSD |
publishDate |
1998 |
url |
https://hal.science/hal-04314576 https://doi.org/10.1139/e98-055 |
genre |
Subarctic |
genre_facet |
Subarctic |
op_source |
ISSN: 0008-4077 EISSN: 1480-3313 Canadian journal of earth sciences https://hal.science/hal-04314576 Canadian journal of earth sciences, 1998, 35 (9), pp.965-979. ⟨10.1139/e98-055⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1139/e98-055 hal-04314576 https://hal.science/hal-04314576 doi:10.1139/e98-055 |
op_doi |
https://doi.org/10.1139/e98-055 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
35 |
container_issue |
9 |
container_start_page |
965 |
op_container_end_page |
979 |
_version_ |
1786835166129291264 |