Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions
High‐resolution shallow sub‐bottom seismic survey data obtained for the Dudgeon windfarm site located 50 km offshore of the north Norfolk coast in the southern North Sea have revealed that the chalk bedrock in this area is overlain by sediments deposited during the Elsterian and Weichselian glacial...
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Online Access: | http://nora.nerc.ac.uk/id/eprint/526144/ https://doi.org/10.1111/bor.12410 |
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ftnerc:oai:nora.nerc.ac.uk:526144 2023-05-15T16:40:20+02:00 Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions Mellett, Claire L. Phillips, Emrys Lee, Jonathan R. Cotterill, Carol J. Tjelta, Tor Inge James, Leo Duffy, Callum 2020-01 http://nora.nerc.ac.uk/id/eprint/526144/ https://doi.org/10.1111/bor.12410 unknown Wiley Mellett, Claire L.; Phillips, Emrys; Lee, Jonathan R.; Cotterill, Carol J.; Tjelta, Tor Inge; James, Leo; Duffy, Callum. 2020 Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions. Boreas, 49 (1). 129-151. https://doi.org/10.1111/bor.12410 <https://doi.org/10.1111/bor.12410> Publication - Article PeerReviewed 2020 ftnerc https://doi.org/10.1111/bor.12410 2023-02-04T19:49:47Z High‐resolution shallow sub‐bottom seismic survey data obtained for the Dudgeon windfarm site located 50 km offshore of the north Norfolk coast in the southern North Sea have revealed that the chalk bedrock in this area is overlain by sediments deposited during the Elsterian and Weichselian glacial periods. A buried N–S‐trending subglacial drainage channel (tunnel valley) filled with Swarte Bank Formation (MIS 12) sediments indicates that the maximum extent of the Elsterian ice‐sheet margin occurred further to the south. Detailed cross‐sections constructed from the seismic data reveal the presence of buried thrust‐block moraine system composed of deformed (folded and thrusted) Swarte Bank Formation sediments, lying beneath a younger sequence of sediments dominated by the glacigenic Bolders Bank Formation (MIS 2). The geometry of the folds and sense of offset on the thrusts, coupled with the morphology of the ridge‐like landforms within this buried moraine system, are consistent with deformation having occurred in response to ice‐push from the N/NE. The chalk bedrock that underlies the glaciotectonized sequence is thought to have provided an antecedent control on the location and preservation of this moraine system. A three‐phase model is proposed to explain the evolution of this thrust‐moraine complex that formed at the oscillating ice margin during the overall active retreat of the Elsterian ice sheet. Article in Journal/Newspaper Ice Sheet Natural Environment Research Council: NERC Open Research Archive Boreas 49 1 129 151 |
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Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
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ftnerc |
language |
unknown |
description |
High‐resolution shallow sub‐bottom seismic survey data obtained for the Dudgeon windfarm site located 50 km offshore of the north Norfolk coast in the southern North Sea have revealed that the chalk bedrock in this area is overlain by sediments deposited during the Elsterian and Weichselian glacial periods. A buried N–S‐trending subglacial drainage channel (tunnel valley) filled with Swarte Bank Formation (MIS 12) sediments indicates that the maximum extent of the Elsterian ice‐sheet margin occurred further to the south. Detailed cross‐sections constructed from the seismic data reveal the presence of buried thrust‐block moraine system composed of deformed (folded and thrusted) Swarte Bank Formation sediments, lying beneath a younger sequence of sediments dominated by the glacigenic Bolders Bank Formation (MIS 2). The geometry of the folds and sense of offset on the thrusts, coupled with the morphology of the ridge‐like landforms within this buried moraine system, are consistent with deformation having occurred in response to ice‐push from the N/NE. The chalk bedrock that underlies the glaciotectonized sequence is thought to have provided an antecedent control on the location and preservation of this moraine system. A three‐phase model is proposed to explain the evolution of this thrust‐moraine complex that formed at the oscillating ice margin during the overall active retreat of the Elsterian ice sheet. |
format |
Article in Journal/Newspaper |
author |
Mellett, Claire L. Phillips, Emrys Lee, Jonathan R. Cotterill, Carol J. Tjelta, Tor Inge James, Leo Duffy, Callum |
spellingShingle |
Mellett, Claire L. Phillips, Emrys Lee, Jonathan R. Cotterill, Carol J. Tjelta, Tor Inge James, Leo Duffy, Callum Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions |
author_facet |
Mellett, Claire L. Phillips, Emrys Lee, Jonathan R. Cotterill, Carol J. Tjelta, Tor Inge James, Leo Duffy, Callum |
author_sort |
Mellett, Claire L. |
title |
Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions |
title_short |
Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions |
title_full |
Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions |
title_fullStr |
Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions |
title_full_unstemmed |
Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions |
title_sort |
elsterian ice‐sheet retreat in the southern north sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions |
publisher |
Wiley |
publishDate |
2020 |
url |
http://nora.nerc.ac.uk/id/eprint/526144/ https://doi.org/10.1111/bor.12410 |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
Mellett, Claire L.; Phillips, Emrys; Lee, Jonathan R.; Cotterill, Carol J.; Tjelta, Tor Inge; James, Leo; Duffy, Callum. 2020 Elsterian ice‐sheet retreat in the southern North Sea: antecedent controls on large‐scale glaciotectonics and subglacial bed conditions. Boreas, 49 (1). 129-151. https://doi.org/10.1111/bor.12410 <https://doi.org/10.1111/bor.12410> |
op_doi |
https://doi.org/10.1111/bor.12410 |
container_title |
Boreas |
container_volume |
49 |
container_issue |
1 |
container_start_page |
129 |
op_container_end_page |
151 |
_version_ |
1766030720895025152 |