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 flow 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: | http://nora.nerc.ac.uk/id/eprint/504940/ https://nora.nerc.ac.uk/id/eprint/504940/1/Geology-2014-Carter-G35091.1.pdf https://doi.org/10.1130/G35091.1 |
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ftnerc:oai:nora.nerc.ac.uk:504940 2023-05-15T13:48:08+02:00 Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow Carter, Andrew Curtis, Mike Schwanethal, James 2014-04-01 text http://nora.nerc.ac.uk/id/eprint/504940/ https://nora.nerc.ac.uk/id/eprint/504940/1/Geology-2014-Carter-G35091.1.pdf https://doi.org/10.1130/G35091.1 en eng Geological Society of America https://nora.nerc.ac.uk/id/eprint/504940/1/Geology-2014-Carter-G35091.1.pdf Carter, Andrew; Curtis, Mike; Schwanethal, James. 2014 Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow. Geology, 42 (4). 299-302. https://doi.org/10.1130/G35091.1 <https://doi.org/10.1130/G35091.1> cc_by CC-BY Publication - Article PeerReviewed 2014 ftnerc https://doi.org/10.1130/G35091.1 2023-02-04T19:38:38Z 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 flow 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 Natural Environment Research Council: NERC Open Research Archive Antarctic Scotia Sea Pacific Rocas ENVELOPE(-56.948,-56.948,-63.398,-63.398) North Scotia Ridge ENVELOPE(-51.431,-51.431,-53.581,-53.581) West Scotia Ridge ENVELOPE(-56.500,-56.500,-56.833,-56.833) Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) Northeast Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) Geology 42 4 299 302 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
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 flow 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, Mike Schwanethal, James |
spellingShingle |
Carter, Andrew Curtis, Mike Schwanethal, James Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow |
author_facet |
Carter, Andrew Curtis, Mike Schwanethal, James |
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 |
http://nora.nerc.ac.uk/id/eprint/504940/ https://nora.nerc.ac.uk/id/eprint/504940/1/Geology-2014-Carter-G35091.1.pdf https://doi.org/10.1130/G35091.1 |
long_lat |
ENVELOPE(-56.948,-56.948,-63.398,-63.398) ENVELOPE(-51.431,-51.431,-53.581,-53.581) ENVELOPE(-56.500,-56.500,-56.833,-56.833) ENVELOPE(-32.500,-32.500,-52.500,-52.500) ENVELOPE(-32.500,-32.500,-52.500,-52.500) |
geographic |
Antarctic Scotia Sea Pacific Rocas North Scotia Ridge West Scotia Ridge Georgia Rise Northeast Georgia Rise |
geographic_facet |
Antarctic Scotia Sea Pacific Rocas North Scotia Ridge West Scotia Ridge Georgia Rise Northeast Georgia Rise |
genre |
Antarc* Antarctic Antarctica Scotia Sea |
genre_facet |
Antarc* Antarctic Antarctica Scotia Sea |
op_relation |
https://nora.nerc.ac.uk/id/eprint/504940/1/Geology-2014-Carter-G35091.1.pdf Carter, Andrew; Curtis, Mike; Schwanethal, James. 2014 Cenozoic tectonic history of the South Georgia microcontinent and potential as a barrier to Pacific-Atlantic through flow. Geology, 42 (4). 299-302. https://doi.org/10.1130/G35091.1 <https://doi.org/10.1130/G35091.1> |
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 |
_version_ |
1766248741220646912 |