Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why?
During evolution of the South Sandwich subduction zone, which has consumed South American Plate oceanic lithosphere, somehow continental crust of both the South American and Antarctic plates have become incorporated into its upper plate. Continental fragments of both plates are currently separated b...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/472835 2023-11-12T04:08:15+01:00 Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why? van de Lagemaat, Suzanna H.A. Swart, Merel L.A. Vaes, Bram Kosters, Martha E. Boschman, Lydian id_orcid:0 000-0002-1802-0187 Burton-Johnson, Alex Bijl, Peter K. Spakman, Wim van Hinsbergen, Douwe J.J. 2021-04 application/application/pdf https://hdl.handle.net/20.500.11850/472835 https://doi.org/10.3929/ethz-b-000472835 en eng Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.earscirev.2021.103551 info:eu-repo/semantics/altIdentifier/wos/000634962500001 http://hdl.handle.net/20.500.11850/472835 doi:10.3929/ethz-b-000472835 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International Earth-Science Reviews, 215 Scotia Sea Drake Passage Kinematic reconstruction GPLates South Sandwich subduction initiation Lithosphere delamination info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2021 ftethz https://doi.org/20.500.11850/47283510.3929/ethz-b-00047283510.1016/j.earscirev.2021.103551 2023-10-15T23:50:27Z During evolution of the South Sandwich subduction zone, which has consumed South American Plate oceanic lithosphere, somehow continental crust of both the South American and Antarctic plates have become incorporated into its upper plate. Continental fragments of both plates are currently separated by small oceanic basins in the upper plate above the South Sandwich subduction zone, in the Scotia Sea region, but how fragments of both continents became incorporated in the same upper plate remains enigmatic. Here we present an updated kinematic reconstruction of the Scotia Sea region using the latest published marine magnetic anomaly constraints, and place this in a South America-Africa-Antarctica plate circuit in which we take intracontinental deformation into account. We show that a change in marine magnetic anomaly orientation in the Weddell Sea requires that previously inferred initiation of subduction of South American oceanic crust of the northern Weddell Sea below the eastern margin of South Orkney Islands continental crust, then still attached to the Antarctic Peninsula, already occurred around 80 Ma. Subsequently, between ~71–50 Ma, we propose that the trench propagated northwards into South America by delamination of South American lithosphere: this resulted in the transfer of delaminated South American continental crust to the overriding plate of the South Sandwich subduction zone. We show that continental delamination may have been facilitated by absolute southward motion of South America that was resisted by South Sandwich slab dragging. Pre-drift extension preceding the oceanic Scotia Sea basins led around 50 Ma to opening of the Drake Passage, preconditioning the southern ocean for the Antarctic Circumpolar Current. This 50 Ma extension was concurrent with a strong change in absolute plate motion of the South American Plate that changed from S to WNW, leading to upper plate retreat relative to the more or less mantle stationary South Sandwich Trench that did not partake in the absolute plate motion ... Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Drake Passage Scotia Sea South Orkney Islands Southern Ocean Weddell Sea ETH Zürich Research Collection Antarctic Antarctic Peninsula Drake Passage Scotia Sea South Orkney Islands ENVELOPE(-45.500,-45.500,-60.583,-60.583) South Sandwich Trench ENVELOPE(-25.000,-25.000,-56.500,-56.500) Southern Ocean The Antarctic Weddell Weddell Sea |
institution |
Open Polar |
collection |
ETH Zürich Research Collection |
op_collection_id |
ftethz |
language |
English |
topic |
Scotia Sea Drake Passage Kinematic reconstruction GPLates South Sandwich subduction initiation Lithosphere delamination |
spellingShingle |
Scotia Sea Drake Passage Kinematic reconstruction GPLates South Sandwich subduction initiation Lithosphere delamination van de Lagemaat, Suzanna H.A. Swart, Merel L.A. Vaes, Bram Kosters, Martha E. Boschman, Lydian id_orcid:0 000-0002-1802-0187 Burton-Johnson, Alex Bijl, Peter K. Spakman, Wim van Hinsbergen, Douwe J.J. Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why? |
topic_facet |
Scotia Sea Drake Passage Kinematic reconstruction GPLates South Sandwich subduction initiation Lithosphere delamination |
description |
During evolution of the South Sandwich subduction zone, which has consumed South American Plate oceanic lithosphere, somehow continental crust of both the South American and Antarctic plates have become incorporated into its upper plate. Continental fragments of both plates are currently separated by small oceanic basins in the upper plate above the South Sandwich subduction zone, in the Scotia Sea region, but how fragments of both continents became incorporated in the same upper plate remains enigmatic. Here we present an updated kinematic reconstruction of the Scotia Sea region using the latest published marine magnetic anomaly constraints, and place this in a South America-Africa-Antarctica plate circuit in which we take intracontinental deformation into account. We show that a change in marine magnetic anomaly orientation in the Weddell Sea requires that previously inferred initiation of subduction of South American oceanic crust of the northern Weddell Sea below the eastern margin of South Orkney Islands continental crust, then still attached to the Antarctic Peninsula, already occurred around 80 Ma. Subsequently, between ~71–50 Ma, we propose that the trench propagated northwards into South America by delamination of South American lithosphere: this resulted in the transfer of delaminated South American continental crust to the overriding plate of the South Sandwich subduction zone. We show that continental delamination may have been facilitated by absolute southward motion of South America that was resisted by South Sandwich slab dragging. Pre-drift extension preceding the oceanic Scotia Sea basins led around 50 Ma to opening of the Drake Passage, preconditioning the southern ocean for the Antarctic Circumpolar Current. This 50 Ma extension was concurrent with a strong change in absolute plate motion of the South American Plate that changed from S to WNW, leading to upper plate retreat relative to the more or less mantle stationary South Sandwich Trench that did not partake in the absolute plate motion ... |
format |
Article in Journal/Newspaper |
author |
van de Lagemaat, Suzanna H.A. Swart, Merel L.A. Vaes, Bram Kosters, Martha E. Boschman, Lydian id_orcid:0 000-0002-1802-0187 Burton-Johnson, Alex Bijl, Peter K. Spakman, Wim van Hinsbergen, Douwe J.J. |
author_facet |
van de Lagemaat, Suzanna H.A. Swart, Merel L.A. Vaes, Bram Kosters, Martha E. Boschman, Lydian id_orcid:0 000-0002-1802-0187 Burton-Johnson, Alex Bijl, Peter K. Spakman, Wim van Hinsbergen, Douwe J.J. |
author_sort |
van de Lagemaat, Suzanna H.A. |
title |
Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why? |
title_short |
Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why? |
title_full |
Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why? |
title_fullStr |
Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why? |
title_full_unstemmed |
Subduction initiation in the Scotia Sea region and opening of the Drake Passage: When and why? |
title_sort |
subduction initiation in the scotia sea region and opening of the drake passage: when and why? |
publisher |
Elsevier |
publishDate |
2021 |
url |
https://hdl.handle.net/20.500.11850/472835 https://doi.org/10.3929/ethz-b-000472835 |
long_lat |
ENVELOPE(-45.500,-45.500,-60.583,-60.583) ENVELOPE(-25.000,-25.000,-56.500,-56.500) |
geographic |
Antarctic Antarctic Peninsula Drake Passage Scotia Sea South Orkney Islands South Sandwich Trench Southern Ocean The Antarctic Weddell Weddell Sea |
geographic_facet |
Antarctic Antarctic Peninsula Drake Passage Scotia Sea South Orkney Islands South Sandwich Trench Southern Ocean The Antarctic Weddell Weddell Sea |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Drake Passage Scotia Sea South Orkney Islands Southern Ocean Weddell Sea |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Drake Passage Scotia Sea South Orkney Islands Southern Ocean Weddell Sea |
op_source |
Earth-Science Reviews, 215 |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.earscirev.2021.103551 info:eu-repo/semantics/altIdentifier/wos/000634962500001 http://hdl.handle.net/20.500.11850/472835 doi:10.3929/ethz-b-000472835 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International |
op_doi |
https://doi.org/20.500.11850/47283510.3929/ethz-b-00047283510.1016/j.earscirev.2021.103551 |
_version_ |
1782328599307616256 |