Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup
The origin of the submarine Naturaliste Plateau off the southwestern coast of Australia is controversial; previous work supports both oceanic and continental affinities for the basement to volcanic and sedimentary sequences. We report the first evidence of reworked Mesoproterozoic (ca. 1230–1190 Ma)...
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2008
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ftnerc:oai:nora.nerc.ac.uk:163542 2023-05-15T13:48:07+02:00 Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup Halpin, Jacqueline A. Crawford, Anthony J. Direen, Nicholas G. Coffin, Millard F. Forbes, Caroline J. Borissova, Irina 2008-10 http://nora.nerc.ac.uk/id/eprint/163542/ http://www.gsajournals.org/perlserv/?request=get-document&doi=10.1130%2FG25059A.1 https://doi.org/10.1130/G25059A.1 unknown Halpin, Jacqueline A.; Crawford, Anthony J.; Direen, Nicholas G.; Coffin, Millard F.; Forbes, Caroline J.; Borissova, Irina. 2008 Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup. Geology, 36 (10). 807-810. https://doi.org/10.1130/G25059A.1 <https://doi.org/10.1130/G25059A.1> Publication - Article PeerReviewed 2008 ftnerc https://doi.org/10.1130/G25059A.1 2023-02-04T19:35:21Z The origin of the submarine Naturaliste Plateau off the southwestern coast of Australia is controversial; previous work supports both oceanic and continental affinities for the basement to volcanic and sedimentary sequences. We report the first evidence of reworked Mesoproterozoic (ca. 1230–1190 Ma) continental crust, based on laser ablation–inductively coupled plasma–mass spectrometry analysis of zircons from granite and orthogneiss samples dredged from the southern margin of the plateau. Thermobarometry of peak metamorphic minerals and electron microprobe chemical dating of monazite reveal that these igneous rocks were metamorphosed to ~700 °C and ~6.5 kbar during the Cambrian Pinjarra Orogeny at ca. 515 Ma. These data confirm a continental origin for a significant swathe of the southern Naturaliste Plateau, and suggest that the protoliths may have affinities to Mesoproterozoic crust within the Albany-Fraser-Wilkes Orogen (Australia-Antarctica). The present Naturaliste Plateau basement beneath its volcanic carapace probably represents a middle-to lower-crustal extensional allochthon exhumed during Cretaceous hyperextensional breakup between Australia and Antarctica. Article in Journal/Newspaper Antarc* Antarctica Natural Environment Research Council: NERC Open Research Archive Geology 36 10 807 |
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Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
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ftnerc |
language |
unknown |
description |
The origin of the submarine Naturaliste Plateau off the southwestern coast of Australia is controversial; previous work supports both oceanic and continental affinities for the basement to volcanic and sedimentary sequences. We report the first evidence of reworked Mesoproterozoic (ca. 1230–1190 Ma) continental crust, based on laser ablation–inductively coupled plasma–mass spectrometry analysis of zircons from granite and orthogneiss samples dredged from the southern margin of the plateau. Thermobarometry of peak metamorphic minerals and electron microprobe chemical dating of monazite reveal that these igneous rocks were metamorphosed to ~700 °C and ~6.5 kbar during the Cambrian Pinjarra Orogeny at ca. 515 Ma. These data confirm a continental origin for a significant swathe of the southern Naturaliste Plateau, and suggest that the protoliths may have affinities to Mesoproterozoic crust within the Albany-Fraser-Wilkes Orogen (Australia-Antarctica). The present Naturaliste Plateau basement beneath its volcanic carapace probably represents a middle-to lower-crustal extensional allochthon exhumed during Cretaceous hyperextensional breakup between Australia and Antarctica. |
format |
Article in Journal/Newspaper |
author |
Halpin, Jacqueline A. Crawford, Anthony J. Direen, Nicholas G. Coffin, Millard F. Forbes, Caroline J. Borissova, Irina |
spellingShingle |
Halpin, Jacqueline A. Crawford, Anthony J. Direen, Nicholas G. Coffin, Millard F. Forbes, Caroline J. Borissova, Irina Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup |
author_facet |
Halpin, Jacqueline A. Crawford, Anthony J. Direen, Nicholas G. Coffin, Millard F. Forbes, Caroline J. Borissova, Irina |
author_sort |
Halpin, Jacqueline A. |
title |
Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup |
title_short |
Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup |
title_full |
Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup |
title_fullStr |
Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup |
title_full_unstemmed |
Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup |
title_sort |
naturaliste plateau, offshore western australia: a submarine window into gondwana assembly and breakup |
publishDate |
2008 |
url |
http://nora.nerc.ac.uk/id/eprint/163542/ http://www.gsajournals.org/perlserv/?request=get-document&doi=10.1130%2FG25059A.1 https://doi.org/10.1130/G25059A.1 |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_relation |
Halpin, Jacqueline A.; Crawford, Anthony J.; Direen, Nicholas G.; Coffin, Millard F.; Forbes, Caroline J.; Borissova, Irina. 2008 Naturaliste Plateau, offshore Western Australia: a submarine window into Gondwana assembly and breakup. Geology, 36 (10). 807-810. https://doi.org/10.1130/G25059A.1 <https://doi.org/10.1130/G25059A.1> |
op_doi |
https://doi.org/10.1130/G25059A.1 |
container_title |
Geology |
container_volume |
36 |
container_issue |
10 |
container_start_page |
807 |
_version_ |
1766248617307275264 |