A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK
Recent investigations from modern environments demonstrate that many terminal moraines do not simply record a single glacial maximum, but instead reveal a complex oscillatory pattern of ice-marginal behaviour including polyphase retreat. Within this study, we examine the geomorphology, geology and i...
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ftnerc:oai:nora.nerc.ac.uk:503109 2023-05-15T16:40:42+02:00 A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK Lee, Jonathan R. Phillips, Emrys Booth, Stephen J. Rose, James Jordan, Hannah M. Pawley, Steven M. Warren, Martin Lawley, Russell S. 2013-08-29 text http://nora.nerc.ac.uk/id/eprint/503109/ https://nora.nerc.ac.uk/id/eprint/503109/1/Lee_et_al_2013_PGA.pdf http://www.sciencedirect.com/science/article/pii/S0016787813000643 en eng Elsevier https://nora.nerc.ac.uk/id/eprint/503109/1/Lee_et_al_2013_PGA.pdf Lee, Jonathan R.; Phillips, Emrys; Booth, Stephen J.; Rose, James; Jordan, Hannah M.; Pawley, Steven M.; Warren, Martin; Lawley, Russell S. 2013 A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK. Proceedings of the Geologists' Association, 124 (5). 753-777. https://doi.org/10.1016/j.pgeola.2013.07.002 <https://doi.org/10.1016/j.pgeola.2013.07.002> Earth Sciences Publication - Article PeerReviewed 2013 ftnerc https://doi.org/10.1016/j.pgeola.2013.07.002 2023-02-04T19:37:38Z Recent investigations from modern environments demonstrate that many terminal moraines do not simply record a single glacial maximum, but instead reveal a complex oscillatory pattern of ice-marginal behaviour including polyphase retreat. Within this study, we examine the geomorphology, geology and internal structure of a terminal moraine complex – the ‘Cromer Ridge’ in north Norfolk to reconstruct patterns of ice-marginal behaviour. Previously, this landform was interpreted as the limit of a southern extension of the British Ice Sheet during a Middle Pleistocene glaciation. Evidence presented here reveals a more complicated pattern of ice-marginal behaviour with the ‘Cromer Ridge’ reinterpreted as a ‘complex’ comprising several ridge elements. We propose that the maximum ice extent lay further to the south, with the size and morphology of the largest ridge element (the ‘Cromer Ridge’ as previously defined) a facet of thrust-stacking at an ice-marginal still-stand. We recognise multiple oscillations of the ice-front recorded against a twelve-stage model for the decay of the southern margins of a fast-flowing lobe of North Sea ice. Changes in ice-marginal dynamics are identified by the superimposition and lateral and vertical evolution of glacitectonic styles. Differences between these various states, and switches between ‘shallow’ and ‘deep’ thin-skinned glacitectonics, are strongly influenced by sub-marginal and proglacial water availability. Examination of the evidence for the morphostratigraphic proposals for the glacitectonic assemblage, within the context of the above interpretation, suggests that many of the ‘glacigenic landforms’ are erosional and a MIS 12 age of formation is favoured although several anomalies remain to be explained. Article in Journal/Newspaper Ice Sheet Sea ice Natural Environment Research Council: NERC Open Research Archive Proceedings of the Geologists' Association 124 5 753 777 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
topic |
Earth Sciences |
spellingShingle |
Earth Sciences Lee, Jonathan R. Phillips, Emrys Booth, Stephen J. Rose, James Jordan, Hannah M. Pawley, Steven M. Warren, Martin Lawley, Russell S. A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK |
topic_facet |
Earth Sciences |
description |
Recent investigations from modern environments demonstrate that many terminal moraines do not simply record a single glacial maximum, but instead reveal a complex oscillatory pattern of ice-marginal behaviour including polyphase retreat. Within this study, we examine the geomorphology, geology and internal structure of a terminal moraine complex – the ‘Cromer Ridge’ in north Norfolk to reconstruct patterns of ice-marginal behaviour. Previously, this landform was interpreted as the limit of a southern extension of the British Ice Sheet during a Middle Pleistocene glaciation. Evidence presented here reveals a more complicated pattern of ice-marginal behaviour with the ‘Cromer Ridge’ reinterpreted as a ‘complex’ comprising several ridge elements. We propose that the maximum ice extent lay further to the south, with the size and morphology of the largest ridge element (the ‘Cromer Ridge’ as previously defined) a facet of thrust-stacking at an ice-marginal still-stand. We recognise multiple oscillations of the ice-front recorded against a twelve-stage model for the decay of the southern margins of a fast-flowing lobe of North Sea ice. Changes in ice-marginal dynamics are identified by the superimposition and lateral and vertical evolution of glacitectonic styles. Differences between these various states, and switches between ‘shallow’ and ‘deep’ thin-skinned glacitectonics, are strongly influenced by sub-marginal and proglacial water availability. Examination of the evidence for the morphostratigraphic proposals for the glacitectonic assemblage, within the context of the above interpretation, suggests that many of the ‘glacigenic landforms’ are erosional and a MIS 12 age of formation is favoured although several anomalies remain to be explained. |
format |
Article in Journal/Newspaper |
author |
Lee, Jonathan R. Phillips, Emrys Booth, Stephen J. Rose, James Jordan, Hannah M. Pawley, Steven M. Warren, Martin Lawley, Russell S. |
author_facet |
Lee, Jonathan R. Phillips, Emrys Booth, Stephen J. Rose, James Jordan, Hannah M. Pawley, Steven M. Warren, Martin Lawley, Russell S. |
author_sort |
Lee, Jonathan R. |
title |
A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK |
title_short |
A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK |
title_full |
A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK |
title_fullStr |
A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK |
title_full_unstemmed |
A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK |
title_sort |
polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the middle pleistocene british ice sheet, northern norfolk, uk |
publisher |
Elsevier |
publishDate |
2013 |
url |
http://nora.nerc.ac.uk/id/eprint/503109/ https://nora.nerc.ac.uk/id/eprint/503109/1/Lee_et_al_2013_PGA.pdf http://www.sciencedirect.com/science/article/pii/S0016787813000643 |
genre |
Ice Sheet Sea ice |
genre_facet |
Ice Sheet Sea ice |
op_relation |
https://nora.nerc.ac.uk/id/eprint/503109/1/Lee_et_al_2013_PGA.pdf Lee, Jonathan R.; Phillips, Emrys; Booth, Stephen J.; Rose, James; Jordan, Hannah M.; Pawley, Steven M.; Warren, Martin; Lawley, Russell S. 2013 A polyphase glacitectonic model for ice-marginal retreat and terminal moraine development: the Middle Pleistocene British Ice Sheet, northern Norfolk, UK. Proceedings of the Geologists' Association, 124 (5). 753-777. https://doi.org/10.1016/j.pgeola.2013.07.002 <https://doi.org/10.1016/j.pgeola.2013.07.002> |
op_doi |
https://doi.org/10.1016/j.pgeola.2013.07.002 |
container_title |
Proceedings of the Geologists' Association |
container_volume |
124 |
container_issue |
5 |
container_start_page |
753 |
op_container_end_page |
777 |
_version_ |
1766031113270067200 |