Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography
Abstract This chapter describes large-scale mantle flow structures beneath Antarctica as derived from global seismic tomography models of the present-day state. In combination with plate reconstructions, the time-dependent pattern of palaeosubduction can be simulated and is shown from the rarely see...
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ftoslouniv:oai:www.duo.uio.no:10852/90532 2023-05-15T14:02:32+02:00 Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography Bredow, Eva Steinberger, Bernhard Gassmöller, Rene Dannberg, Juliane 2021 http://hdl.handle.net/10852/90532 http://urn.nb.no/URN:NBN:no-93116 https://doi.org/10.1144/M56-2020-2 EN eng The Geological Society of London NFR/223272 http://urn.nb.no/URN:NBN:no-93116 Bredow, Eva Steinberger, Bernhard Gassmöller, Rene Dannberg, Juliane . Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography. Geological Society of London Memoirs. 2021, 56 http://hdl.handle.net/10852/90532 1982040 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Geological Society of London Memoirs&rft.volume=56&rft.spage=&rft.date=2021 Geological Society of London Memoirs 56 M56-2020 2020-2 https://doi.org/10.1144/M56-2020-2 URN:NBN:no-93116 Fulltext https://www.duo.uio.no/bitstream/handle/10852/90532/1/antarctic_plumes.pdf 0435-4052 Journal article Tidsskriftartikkel Peer reviewed AcceptedVersion 2021 ftoslouniv https://doi.org/10.1144/M56-2020-2 2022-02-09T23:33:49Z Abstract This chapter describes large-scale mantle flow structures beneath Antarctica as derived from global seismic tomography models of the present-day state. In combination with plate reconstructions, the time-dependent pattern of palaeosubduction can be simulated and is shown from the rarely seen Antarctic perspective. Furthermore, a dynamic topography model demonstrates which kind and scales of surface manifestations can be expected as a direct and observable result of mantle convection. The last section of this chapter features an overview of the classical concept of deep-mantle plumes from a geodynamic point of view and how recent insights, mostly from seismic tomography, have changed the understanding of plume structures and dynamics over past decades. The long-standing and controversial hypothesis of a mantle plume beneath West Antarctica is summarized and addressed with geodynamic models, which estimate the excess heat flow of a potential plume at the bedrock surface. However, the predicted heat flow is small, while differences in surface heat-flux estimates are large; therefore, the results are not conclusive with regard to the existence of a West Antarctic mantle plume. Finally, it is shown that global mantle flow would cause the tilting of whole-mantle plume conduits beneath West Antarctica such that their base is predicted to be displaced about 20° northward relative to the surface position, closer to the southern margin of the Pacific Large Low-Shear Velocity Province. Article in Journal/Newspaper Antarc* Antarctic Antarctica West Antarctica Universitet i Oslo: Digitale utgivelser ved UiO (DUO) Antarctic Pacific Tilting ENVELOPE(-54.065,-54.065,49.700,49.700) West Antarctica Geological Society, London, Memoirs 56 1 |
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Open Polar |
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Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
op_collection_id |
ftoslouniv |
language |
English |
description |
Abstract This chapter describes large-scale mantle flow structures beneath Antarctica as derived from global seismic tomography models of the present-day state. In combination with plate reconstructions, the time-dependent pattern of palaeosubduction can be simulated and is shown from the rarely seen Antarctic perspective. Furthermore, a dynamic topography model demonstrates which kind and scales of surface manifestations can be expected as a direct and observable result of mantle convection. The last section of this chapter features an overview of the classical concept of deep-mantle plumes from a geodynamic point of view and how recent insights, mostly from seismic tomography, have changed the understanding of plume structures and dynamics over past decades. The long-standing and controversial hypothesis of a mantle plume beneath West Antarctica is summarized and addressed with geodynamic models, which estimate the excess heat flow of a potential plume at the bedrock surface. However, the predicted heat flow is small, while differences in surface heat-flux estimates are large; therefore, the results are not conclusive with regard to the existence of a West Antarctic mantle plume. Finally, it is shown that global mantle flow would cause the tilting of whole-mantle plume conduits beneath West Antarctica such that their base is predicted to be displaced about 20° northward relative to the surface position, closer to the southern margin of the Pacific Large Low-Shear Velocity Province. |
format |
Article in Journal/Newspaper |
author |
Bredow, Eva Steinberger, Bernhard Gassmöller, Rene Dannberg, Juliane |
spellingShingle |
Bredow, Eva Steinberger, Bernhard Gassmöller, Rene Dannberg, Juliane Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography |
author_facet |
Bredow, Eva Steinberger, Bernhard Gassmöller, Rene Dannberg, Juliane |
author_sort |
Bredow, Eva |
title |
Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography |
title_short |
Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography |
title_full |
Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography |
title_fullStr |
Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography |
title_full_unstemmed |
Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography |
title_sort |
mantle convection and possible mantle plumes beneath antarctica – insights from geodynamic models and implications for topography |
publisher |
The Geological Society of London |
publishDate |
2021 |
url |
http://hdl.handle.net/10852/90532 http://urn.nb.no/URN:NBN:no-93116 https://doi.org/10.1144/M56-2020-2 |
long_lat |
ENVELOPE(-54.065,-54.065,49.700,49.700) |
geographic |
Antarctic Pacific Tilting West Antarctica |
geographic_facet |
Antarctic Pacific Tilting West Antarctica |
genre |
Antarc* Antarctic Antarctica West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica West Antarctica |
op_source |
0435-4052 |
op_relation |
NFR/223272 http://urn.nb.no/URN:NBN:no-93116 Bredow, Eva Steinberger, Bernhard Gassmöller, Rene Dannberg, Juliane . Mantle convection and possible mantle plumes beneath Antarctica – insights from geodynamic models and implications for topography. Geological Society of London Memoirs. 2021, 56 http://hdl.handle.net/10852/90532 1982040 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Geological Society of London Memoirs&rft.volume=56&rft.spage=&rft.date=2021 Geological Society of London Memoirs 56 M56-2020 2020-2 https://doi.org/10.1144/M56-2020-2 URN:NBN:no-93116 Fulltext https://www.duo.uio.no/bitstream/handle/10852/90532/1/antarctic_plumes.pdf |
op_doi |
https://doi.org/10.1144/M56-2020-2 |
container_title |
Geological Society, London, Memoirs |
container_volume |
56 |
container_issue |
1 |
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1766272841812017152 |