Strain patterns in glacitectonically thrusted sediments and conditions during thrusting
International audience Glacitectonically thrusted blocks of unlithified sediment are commonly inferred to have been frozen during thrusting, with implications for paleoclimate and glacier dynamics. We inferred strain patterns within thrusted blocks of glaciolacustrine mud in the Rubjerg Knude and Mø...
Published in: | Journal of Structural Geology |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Online Access: | https://hal.archives-ouvertes.fr/hal-03033129 https://hal.archives-ouvertes.fr/hal-03033129/document https://hal.archives-ouvertes.fr/hal-03033129/file/Warbritton%20et%20al.%20revised%20%28SG_2020_28%29.pdf https://doi.org/10.1016/j.jsg.2020.104064 |
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ftunivnantes:oai:HAL:hal-03033129v1 2023-05-15T17:57:28+02:00 Strain patterns in glacitectonically thrusted sediments and conditions during thrusting Warbritton, Matthew, Iverson, Neal, Lagroix, France Schomacker, Anders Institut de Physique du Globe de Paris (IPGP (UMR_7154)) Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) 2020-08 https://hal.archives-ouvertes.fr/hal-03033129 https://hal.archives-ouvertes.fr/hal-03033129/document https://hal.archives-ouvertes.fr/hal-03033129/file/Warbritton%20et%20al.%20revised%20%28SG_2020_28%29.pdf https://doi.org/10.1016/j.jsg.2020.104064 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jsg.2020.104064 hal-03033129 https://hal.archives-ouvertes.fr/hal-03033129 https://hal.archives-ouvertes.fr/hal-03033129/document https://hal.archives-ouvertes.fr/hal-03033129/file/Warbritton%20et%20al.%20revised%20%28SG_2020_28%29.pdf doi:10.1016/j.jsg.2020.104064 info:eu-repo/semantics/OpenAccess ISSN: 0191-8141 Journal of Structural Geology https://hal.archives-ouvertes.fr/hal-03033129 Journal of Structural Geology, 2020, 137, pp.104064. ⟨10.1016/j.jsg.2020.104064⟩ Glacitectonic deformation Thrust sheets Anisotropy of magnetic susceptibility Permafrost Pore pressure [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics info:eu-repo/semantics/article Journal articles 2020 ftunivnantes https://doi.org/10.1016/j.jsg.2020.104064 2022-12-07T01:12:37Z International audience Glacitectonically thrusted blocks of unlithified sediment are commonly inferred to have been frozen during thrusting, with implications for paleoclimate and glacier dynamics. We inferred strain patterns within thrusted blocks of glaciolacustrine mud in the Rubjerg Knude and Møns Klint glacitectonic complexes of coastal Denmark to try to assess whether the mud was frozen during thrusting. Fabrics based on the anisotropy of magnetic susceptibility (AMS) of the muds are interpreted with results of ring-shear experiments and models of AMS fabric development during layer-parallel shortening (LPS). In intact distal stratigraphy, fabrics indicate moderate LPS. Fabrics where thrusts have disrupted more proximal stratigraphy indicate rotation of mud sheets during thrusting with insufficient penetrative strain to reset the LPS fabric. The exception is within decimeters of faults at Rubjerg Knude where shear overprinted the LPS fabric. Although these data indicate that mud sheets were mostly rigid during thrusting, this is not necessarily evidence of permafrost. Critical-taper theory indicates that even a gentle slope of the proglacial surface away from the glacier margin would have allowed slip without internal deformation of thrust sheets, requiring only minimal pore-water pressures. Article in Journal/Newspaper permafrost Knude Université de Nantes: HAL-UNIV-NANTES Rubjerg Knude ENVELOPE(-23.533,-23.533,72.700,72.700) Journal of Structural Geology 137 104064 |
institution |
Open Polar |
collection |
Université de Nantes: HAL-UNIV-NANTES |
op_collection_id |
ftunivnantes |
language |
English |
topic |
Glacitectonic deformation Thrust sheets Anisotropy of magnetic susceptibility Permafrost Pore pressure [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics |
spellingShingle |
Glacitectonic deformation Thrust sheets Anisotropy of magnetic susceptibility Permafrost Pore pressure [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics Warbritton, Matthew, Iverson, Neal, Lagroix, France Schomacker, Anders Strain patterns in glacitectonically thrusted sediments and conditions during thrusting |
topic_facet |
Glacitectonic deformation Thrust sheets Anisotropy of magnetic susceptibility Permafrost Pore pressure [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics |
description |
International audience Glacitectonically thrusted blocks of unlithified sediment are commonly inferred to have been frozen during thrusting, with implications for paleoclimate and glacier dynamics. We inferred strain patterns within thrusted blocks of glaciolacustrine mud in the Rubjerg Knude and Møns Klint glacitectonic complexes of coastal Denmark to try to assess whether the mud was frozen during thrusting. Fabrics based on the anisotropy of magnetic susceptibility (AMS) of the muds are interpreted with results of ring-shear experiments and models of AMS fabric development during layer-parallel shortening (LPS). In intact distal stratigraphy, fabrics indicate moderate LPS. Fabrics where thrusts have disrupted more proximal stratigraphy indicate rotation of mud sheets during thrusting with insufficient penetrative strain to reset the LPS fabric. The exception is within decimeters of faults at Rubjerg Knude where shear overprinted the LPS fabric. Although these data indicate that mud sheets were mostly rigid during thrusting, this is not necessarily evidence of permafrost. Critical-taper theory indicates that even a gentle slope of the proglacial surface away from the glacier margin would have allowed slip without internal deformation of thrust sheets, requiring only minimal pore-water pressures. |
author2 |
Institut de Physique du Globe de Paris (IPGP (UMR_7154)) Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité) |
format |
Article in Journal/Newspaper |
author |
Warbritton, Matthew, Iverson, Neal, Lagroix, France Schomacker, Anders |
author_facet |
Warbritton, Matthew, Iverson, Neal, Lagroix, France Schomacker, Anders |
author_sort |
Warbritton, Matthew, |
title |
Strain patterns in glacitectonically thrusted sediments and conditions during thrusting |
title_short |
Strain patterns in glacitectonically thrusted sediments and conditions during thrusting |
title_full |
Strain patterns in glacitectonically thrusted sediments and conditions during thrusting |
title_fullStr |
Strain patterns in glacitectonically thrusted sediments and conditions during thrusting |
title_full_unstemmed |
Strain patterns in glacitectonically thrusted sediments and conditions during thrusting |
title_sort |
strain patterns in glacitectonically thrusted sediments and conditions during thrusting |
publisher |
HAL CCSD |
publishDate |
2020 |
url |
https://hal.archives-ouvertes.fr/hal-03033129 https://hal.archives-ouvertes.fr/hal-03033129/document https://hal.archives-ouvertes.fr/hal-03033129/file/Warbritton%20et%20al.%20revised%20%28SG_2020_28%29.pdf https://doi.org/10.1016/j.jsg.2020.104064 |
long_lat |
ENVELOPE(-23.533,-23.533,72.700,72.700) |
geographic |
Rubjerg Knude |
geographic_facet |
Rubjerg Knude |
genre |
permafrost Knude |
genre_facet |
permafrost Knude |
op_source |
ISSN: 0191-8141 Journal of Structural Geology https://hal.archives-ouvertes.fr/hal-03033129 Journal of Structural Geology, 2020, 137, pp.104064. ⟨10.1016/j.jsg.2020.104064⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jsg.2020.104064 hal-03033129 https://hal.archives-ouvertes.fr/hal-03033129 https://hal.archives-ouvertes.fr/hal-03033129/document https://hal.archives-ouvertes.fr/hal-03033129/file/Warbritton%20et%20al.%20revised%20%28SG_2020_28%29.pdf doi:10.1016/j.jsg.2020.104064 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1016/j.jsg.2020.104064 |
container_title |
Journal of Structural Geology |
container_volume |
137 |
container_start_page |
104064 |
_version_ |
1766165898410852352 |