Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow
Cenozoic opening of the central Scotia Sea involved the tectonic translation of crustal blocks to form the North Scotia Ridge, which today is a major topographic constriction to the fl ow of the deep Antarctic Circumpolar Current that keeps Antarctica thermally isolated from warmer ocean waters. How...
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Geological Society of America
2014
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Online Access: | https://eprints.bbk.ac.uk/id/eprint/12986/ https://eprints.bbk.ac.uk/id/eprint/12986/1/Geology-2014-Carter-299-302.pdf https://doi.org/10.1130/G35091.1 |
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ftbirkbeckcoll:oai:eprints.bbk.ac.uk.oai2:12986 2023-05-15T14:02:04+02:00 Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow Carter, Andrew Curtis, M. Schwanenthal, J. 2014 text https://eprints.bbk.ac.uk/id/eprint/12986/ https://eprints.bbk.ac.uk/id/eprint/12986/1/Geology-2014-Carter-299-302.pdf https://doi.org/10.1130/G35091.1 en eng Geological Society of America https://eprints.bbk.ac.uk/id/eprint/12986/1/Geology-2014-Carter-299-302.pdf Carter, Andrew and Curtis, M. and Schwanenthal, J. (2014) Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow. Geology 42 (4), pp. 299-302. ISSN 0091-7613. cc_by CC-BY Earth and Planetary Sciences Article PeerReviewed 2014 ftbirkbeckcoll https://doi.org/10.1130/G35091.1 2022-01-09T08:56:36Z Cenozoic opening of the central Scotia Sea involved the tectonic translation of crustal blocks to form the North Scotia Ridge, which today is a major topographic constriction to the fl ow of the deep Antarctic Circumpolar Current that keeps Antarctica thermally isolated from warmer ocean waters. How this ridge developed and whether it was a topographic barrier in the past are unknown. To address this we investigated the Cenozoic history of the South Georgia microcontinental block, the exposed part of the ridge. Detrital zircon U-Pb geochronology data confirm that the Cretaceous succession of turbidites exposed on South Georgia was stratigraphically connected to the Rocas Verdes backarc basin, part of the South America plate. Apatite thermochronometry results show that South Georgia had remained connected to South America until ca. 45–40 Ma; both record a distinct rapid cooling event at that time. Subsequent separation from South America was accompanied by kilometer-scale reburial until inversion ca. 10 Ma, coeval with the cessation of spreading at the West Scotia Ridge and collision between the South Georgia block and the Northeast Georgia Rise. Our results show that the South Georgia microcontinental block could not have been an emergent feature from ca. 40 Ma until 10 Ma. Article in Journal/Newspaper Antarc* Antarctic Antarctica Scotia Sea BIROn - Birkbeck Institutional Research Online (Birkbeck University of London) Antarctic Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) North Scotia Ridge ENVELOPE(-51.431,-51.431,-53.581,-53.581) Northeast Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) Pacific Rocas ENVELOPE(-56.948,-56.948,-63.398,-63.398) Scotia Sea West Scotia Ridge ENVELOPE(-56.500,-56.500,-56.833,-56.833) Geology 42 4 299 302 |
institution |
Open Polar |
collection |
BIROn - Birkbeck Institutional Research Online (Birkbeck University of London) |
op_collection_id |
ftbirkbeckcoll |
language |
English |
topic |
Earth and Planetary Sciences |
spellingShingle |
Earth and Planetary Sciences Carter, Andrew Curtis, M. Schwanenthal, J. Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow |
topic_facet |
Earth and Planetary Sciences |
description |
Cenozoic opening of the central Scotia Sea involved the tectonic translation of crustal blocks to form the North Scotia Ridge, which today is a major topographic constriction to the fl ow of the deep Antarctic Circumpolar Current that keeps Antarctica thermally isolated from warmer ocean waters. How this ridge developed and whether it was a topographic barrier in the past are unknown. To address this we investigated the Cenozoic history of the South Georgia microcontinental block, the exposed part of the ridge. Detrital zircon U-Pb geochronology data confirm that the Cretaceous succession of turbidites exposed on South Georgia was stratigraphically connected to the Rocas Verdes backarc basin, part of the South America plate. Apatite thermochronometry results show that South Georgia had remained connected to South America until ca. 45–40 Ma; both record a distinct rapid cooling event at that time. Subsequent separation from South America was accompanied by kilometer-scale reburial until inversion ca. 10 Ma, coeval with the cessation of spreading at the West Scotia Ridge and collision between the South Georgia block and the Northeast Georgia Rise. Our results show that the South Georgia microcontinental block could not have been an emergent feature from ca. 40 Ma until 10 Ma. |
format |
Article in Journal/Newspaper |
author |
Carter, Andrew Curtis, M. Schwanenthal, J. |
author_facet |
Carter, Andrew Curtis, M. Schwanenthal, J. |
author_sort |
Carter, Andrew |
title |
Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow |
title_short |
Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow |
title_full |
Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow |
title_fullStr |
Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow |
title_full_unstemmed |
Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow |
title_sort |
cenozoic tectonic history of the south georgia microcontinent and potential as a barrier to pacific-atlantic through flow |
publisher |
Geological Society of America |
publishDate |
2014 |
url |
https://eprints.bbk.ac.uk/id/eprint/12986/ https://eprints.bbk.ac.uk/id/eprint/12986/1/Geology-2014-Carter-299-302.pdf https://doi.org/10.1130/G35091.1 |
long_lat |
ENVELOPE(-32.500,-32.500,-52.500,-52.500) ENVELOPE(-51.431,-51.431,-53.581,-53.581) ENVELOPE(-32.500,-32.500,-52.500,-52.500) ENVELOPE(-56.948,-56.948,-63.398,-63.398) ENVELOPE(-56.500,-56.500,-56.833,-56.833) |
geographic |
Antarctic Georgia Rise North Scotia Ridge Northeast Georgia Rise Pacific Rocas Scotia Sea West Scotia Ridge |
geographic_facet |
Antarctic Georgia Rise North Scotia Ridge Northeast Georgia Rise Pacific Rocas Scotia Sea West Scotia Ridge |
genre |
Antarc* Antarctic Antarctica Scotia Sea |
genre_facet |
Antarc* Antarctic Antarctica Scotia Sea |
op_relation |
https://eprints.bbk.ac.uk/id/eprint/12986/1/Geology-2014-Carter-299-302.pdf Carter, Andrew and Curtis, M. and Schwanenthal, J. (2014) Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow. Geology 42 (4), pp. 299-302. ISSN 0091-7613. |
op_rights |
cc_by |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1130/G35091.1 |
container_title |
Geology |
container_volume |
42 |
container_issue |
4 |
container_start_page |
299 |
op_container_end_page |
302 |
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1766272151579525120 |