Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics.
23 pages International audience Subglacial meltwater drainage and sedimentary processes play a major role in ice-sheet dynamic but there is a lack of study of subglacial environment because modern ice-sheet beds remain inaccessible. Previous authors already intended to provide diagnostic criterion a...
Published in: | Quaternary Science Reviews |
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Online Access: | https://hal.archives-ouvertes.fr/hal-00663941 https://doi.org/10.1016/j.quascirev.2011.12.004 |
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ftccsdartic:oai:HAL:hal-00663941v1 2023-05-15T16:40:46+02:00 Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics. Clerc, Sylvain Buoncristiani, Jean-François Guiraud, Michel Desaubliaux, Guy Portier, Eric Biogéosciences UMR 6282 Dijon (BGS) Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement Direction Exploration Production Gaz de France Suez (GDF Suez) Funding from GDF Suez E&P Division. 2012-02-06 https://hal.archives-ouvertes.fr/hal-00663941 https://doi.org/10.1016/j.quascirev.2011.12.004 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.quascirev.2011.12.004 hal-00663941 https://hal.archives-ouvertes.fr/hal-00663941 doi:10.1016/j.quascirev.2011.12.004 ISSN: 0277-3791 Quaternary Science Reviews https://hal.archives-ouvertes.fr/hal-00663941 Quaternary Science Reviews, Elsevier, 2012, 33, pp.142-164. ⟨10.1016/j.quascirev.2011.12.004⟩ Ireland Killiney Bay Fluid pressure Subglacial sedimentation Subglacial deformation Dyke Hydrofracturing [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology info:eu-repo/semantics/article Journal articles 2012 ftccsdartic https://doi.org/10.1016/j.quascirev.2011.12.004 2020-12-26T05:05:48Z 23 pages International audience Subglacial meltwater drainage and sedimentary processes play a major role in ice-sheet dynamic but there is a lack of study of subglacial environment because modern ice-sheet beds remain inaccessible. Previous authors already intended to provide diagnostic criterion and recent investigations suggest that fluid pressure variations are a key factor in subglacial environment. This paper investigated the late Devensian sedimentary record in order to describe subglacial sedimentological facies associations and deformation features related to fluid overpressures. We used an integrated approach, based on stratigraphy, sedimentology and deformations styles to demonstrate a subglacial depositional model. The studied interval is composed of stratified gravel and sand interbedded with diamicton and boulder pavement, deposited in depressions formed by irregularity of the upper surface of diamicton. Deformation structures include convolutes, dykes and normal micro-faulting. Dykes show different dip directions from vertical, oblique to subhorizontal from which both directions of shortening and extension can be determined. Vertical dykes are formed under pure shear strain related to ice weight only. Oblique dykes imply both ice-bed coupling and simple shear strain between ice and substrate induced by flowing ice related to progressively increasing meltwater drainage intensity. Horizontal dykes are formed when minimum strain is vertical and therefore the overpressure exceeds the weight of overburden. They are associated with high meltwater drainage intensity and ice-bed uncoupling and refer to hydrofracturing. Overall, depositional and deformation sequence also illustrates the increasing intensity of meltwater drainage in small cavity as high energy channelised deposits, and in large cavities where subaqueous fan are deposited under hydraulic jump conditions. Moreover, large cavities represent lee-side cavities formed by fast-flowing ice over an obstacle. Hydrofracturing is likely to occur ... Article in Journal/Newspaper Ice Sheet Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Boulder Pavement ENVELOPE(161.756,161.756,-77.523,-77.523) Quaternary Science Reviews 33 142 164 |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
Ireland Killiney Bay Fluid pressure Subglacial sedimentation Subglacial deformation Dyke Hydrofracturing [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
spellingShingle |
Ireland Killiney Bay Fluid pressure Subglacial sedimentation Subglacial deformation Dyke Hydrofracturing [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology Clerc, Sylvain Buoncristiani, Jean-François Guiraud, Michel Desaubliaux, Guy Portier, Eric Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics. |
topic_facet |
Ireland Killiney Bay Fluid pressure Subglacial sedimentation Subglacial deformation Dyke Hydrofracturing [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
description |
23 pages International audience Subglacial meltwater drainage and sedimentary processes play a major role in ice-sheet dynamic but there is a lack of study of subglacial environment because modern ice-sheet beds remain inaccessible. Previous authors already intended to provide diagnostic criterion and recent investigations suggest that fluid pressure variations are a key factor in subglacial environment. This paper investigated the late Devensian sedimentary record in order to describe subglacial sedimentological facies associations and deformation features related to fluid overpressures. We used an integrated approach, based on stratigraphy, sedimentology and deformations styles to demonstrate a subglacial depositional model. The studied interval is composed of stratified gravel and sand interbedded with diamicton and boulder pavement, deposited in depressions formed by irregularity of the upper surface of diamicton. Deformation structures include convolutes, dykes and normal micro-faulting. Dykes show different dip directions from vertical, oblique to subhorizontal from which both directions of shortening and extension can be determined. Vertical dykes are formed under pure shear strain related to ice weight only. Oblique dykes imply both ice-bed coupling and simple shear strain between ice and substrate induced by flowing ice related to progressively increasing meltwater drainage intensity. Horizontal dykes are formed when minimum strain is vertical and therefore the overpressure exceeds the weight of overburden. They are associated with high meltwater drainage intensity and ice-bed uncoupling and refer to hydrofracturing. Overall, depositional and deformation sequence also illustrates the increasing intensity of meltwater drainage in small cavity as high energy channelised deposits, and in large cavities where subaqueous fan are deposited under hydraulic jump conditions. Moreover, large cavities represent lee-side cavities formed by fast-flowing ice over an obstacle. Hydrofracturing is likely to occur ... |
author2 |
Biogéosciences UMR 6282 Dijon (BGS) Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement Direction Exploration Production Gaz de France Suez (GDF Suez) Funding from GDF Suez E&P Division. |
format |
Article in Journal/Newspaper |
author |
Clerc, Sylvain Buoncristiani, Jean-François Guiraud, Michel Desaubliaux, Guy Portier, Eric |
author_facet |
Clerc, Sylvain Buoncristiani, Jean-François Guiraud, Michel Desaubliaux, Guy Portier, Eric |
author_sort |
Clerc, Sylvain |
title |
Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics. |
title_short |
Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics. |
title_full |
Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics. |
title_fullStr |
Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics. |
title_full_unstemmed |
Depositional model in subglacial cavities, Killiney Bay, Ireland. Interactions between sedimentation, deformation and glacial dynamics. |
title_sort |
depositional model in subglacial cavities, killiney bay, ireland. interactions between sedimentation, deformation and glacial dynamics. |
publisher |
HAL CCSD |
publishDate |
2012 |
url |
https://hal.archives-ouvertes.fr/hal-00663941 https://doi.org/10.1016/j.quascirev.2011.12.004 |
long_lat |
ENVELOPE(161.756,161.756,-77.523,-77.523) |
geographic |
Boulder Pavement |
geographic_facet |
Boulder Pavement |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
ISSN: 0277-3791 Quaternary Science Reviews https://hal.archives-ouvertes.fr/hal-00663941 Quaternary Science Reviews, Elsevier, 2012, 33, pp.142-164. ⟨10.1016/j.quascirev.2011.12.004⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.quascirev.2011.12.004 hal-00663941 https://hal.archives-ouvertes.fr/hal-00663941 doi:10.1016/j.quascirev.2011.12.004 |
op_doi |
https://doi.org/10.1016/j.quascirev.2011.12.004 |
container_title |
Quaternary Science Reviews |
container_volume |
33 |
container_start_page |
142 |
op_container_end_page |
164 |
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1766031179266392064 |