The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula
Triassic orthogneisses of the Antarctic Peninsula provide evidence for the Palaeozoic and Mesozoic geological evolution of southern Gondwana within Pangaea. These rocks are sporadically exposed in southeastern Graham Land and northwestern Palmer Land, although reliable geochronological, geochemical...
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ftnerc:oai:nora.nerc.ac.uk:523231 2023-05-15T13:41:43+02:00 The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula Bastias, Joaquin Spikings, Richard Ulianov, Alex Riley, Teal Burton-Johnson, Alex Chiaradia, Massimo Baumgartner, Lucas Hervé, Francisco Bouvier, Anne-Sophie 2020-05 http://nora.nerc.ac.uk/id/eprint/523231/ https://www.sciencedirect.com/science/article/pii/S1342937X19303156?via%3Dihub unknown Elsevier Bastias, Joaquin; Spikings, Richard; Ulianov, Alex; Riley, Teal orcid:0000-0002-3333-5021 Burton-Johnson, Alex orcid:0000-0003-2208-0075 Chiaradia, Massimo; Baumgartner, Lucas; Hervé, Francisco; Bouvier, Anne-Sophie. 2020 The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula. Gondwana Research, 81. 1-20. https://doi.org/10.1016/j.gr.2019.10.018 <https://doi.org/10.1016/j.gr.2019.10.018> Publication - Article PeerReviewed 2020 ftnerc https://doi.org/10.1016/j.gr.2019.10.018 2023-02-04T19:48:18Z Triassic orthogneisses of the Antarctic Peninsula provide evidence for the Palaeozoic and Mesozoic geological evolution of southern Gondwana within Pangaea. These rocks are sporadically exposed in southeastern Graham Land and northwestern Palmer Land, although reliable geochronological, geochemical and isotopic data are sparse. We combine new geochronological (LA-ICP-MS zircon U[sbnd]Pb), geochemical, and zircon (Hf, O) and whole rock isotopic (Nd, Sr and Pb) data to constrain the age and Triassic – Palaeozoic tectonic setting of these rocks. Zircon cores record Palaeozoic arc magmatism between 253 ± 2 and 528 ± 6 Ma, which was mainly located to the west of the Eastern Palmer Land Shear Zone (Central Domain; Vaughan and Storey, 2000). The arc is considered to be an extension of contemporaneous Palaeozoic arcs that have been identified along the Pacific margin of South America and the Thurston Island Block. Regions to the east of the Palmer Land Shear Zone (Eastern Domain, Vaughan and Storey, 2000) were located distal from the Terra Australis Margin, and possibly resided within Sunsas-aged belts within Pangaea. Triassic continental arc, calc-alkaline magmatism during 223–203 Ma modified the crust of the Antarctic Peninsula on both sides of the Eastern Palmer Land Shear Zone. Magmatic sources included igneous and sedimentary crustal material, which formed by crustal reworking during Sunsas- and Braziliano-aged orogenesis, and Palaeozoic arc magmatism. Arc magmatism accompanied sinistral extension which brought both domains into the arc and resulted in steady oceanward migration of the Triassic arc during the Middle – Late Triassic. We propose that sinistral displacement occurred along the Eastern Palmer Land Shear Zone, and this structure was active as early as the Triassic. Finally, we conclude that both the Eastern and Central Domains are autochthonous to Gondwana. © 2019 International Association for Gondwana Research Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Graham Land Palmer Land Thurston Island West Antarctica Natural Environment Research Council: NERC Open Research Archive Antarctic The Antarctic Antarctic Peninsula West Antarctica Pacific Graham Land ENVELOPE(-63.500,-63.500,-66.000,-66.000) Palmer Land ENVELOPE(-65.000,-65.000,-71.500,-71.500) Thurston ENVELOPE(-97.500,-97.500,-71.833,-71.833) Thurston Island ENVELOPE(-99.000,-99.000,-72.167,-72.167) Terra Australis ENVELOPE(-62.900,-62.900,-64.900,-64.900) Gondwana Research 81 1 20 |
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Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
Triassic orthogneisses of the Antarctic Peninsula provide evidence for the Palaeozoic and Mesozoic geological evolution of southern Gondwana within Pangaea. These rocks are sporadically exposed in southeastern Graham Land and northwestern Palmer Land, although reliable geochronological, geochemical and isotopic data are sparse. We combine new geochronological (LA-ICP-MS zircon U[sbnd]Pb), geochemical, and zircon (Hf, O) and whole rock isotopic (Nd, Sr and Pb) data to constrain the age and Triassic – Palaeozoic tectonic setting of these rocks. Zircon cores record Palaeozoic arc magmatism between 253 ± 2 and 528 ± 6 Ma, which was mainly located to the west of the Eastern Palmer Land Shear Zone (Central Domain; Vaughan and Storey, 2000). The arc is considered to be an extension of contemporaneous Palaeozoic arcs that have been identified along the Pacific margin of South America and the Thurston Island Block. Regions to the east of the Palmer Land Shear Zone (Eastern Domain, Vaughan and Storey, 2000) were located distal from the Terra Australis Margin, and possibly resided within Sunsas-aged belts within Pangaea. Triassic continental arc, calc-alkaline magmatism during 223–203 Ma modified the crust of the Antarctic Peninsula on both sides of the Eastern Palmer Land Shear Zone. Magmatic sources included igneous and sedimentary crustal material, which formed by crustal reworking during Sunsas- and Braziliano-aged orogenesis, and Palaeozoic arc magmatism. Arc magmatism accompanied sinistral extension which brought both domains into the arc and resulted in steady oceanward migration of the Triassic arc during the Middle – Late Triassic. We propose that sinistral displacement occurred along the Eastern Palmer Land Shear Zone, and this structure was active as early as the Triassic. Finally, we conclude that both the Eastern and Central Domains are autochthonous to Gondwana. © 2019 International Association for Gondwana Research |
format |
Article in Journal/Newspaper |
author |
Bastias, Joaquin Spikings, Richard Ulianov, Alex Riley, Teal Burton-Johnson, Alex Chiaradia, Massimo Baumgartner, Lucas Hervé, Francisco Bouvier, Anne-Sophie |
spellingShingle |
Bastias, Joaquin Spikings, Richard Ulianov, Alex Riley, Teal Burton-Johnson, Alex Chiaradia, Massimo Baumgartner, Lucas Hervé, Francisco Bouvier, Anne-Sophie The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula |
author_facet |
Bastias, Joaquin Spikings, Richard Ulianov, Alex Riley, Teal Burton-Johnson, Alex Chiaradia, Massimo Baumgartner, Lucas Hervé, Francisco Bouvier, Anne-Sophie |
author_sort |
Bastias, Joaquin |
title |
The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula |
title_short |
The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula |
title_full |
The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula |
title_fullStr |
The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula |
title_full_unstemmed |
The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula |
title_sort |
gondwanan margin in west antarctica: insights from late triassic magmatism of the antarctic peninsula |
publisher |
Elsevier |
publishDate |
2020 |
url |
http://nora.nerc.ac.uk/id/eprint/523231/ https://www.sciencedirect.com/science/article/pii/S1342937X19303156?via%3Dihub |
long_lat |
ENVELOPE(-63.500,-63.500,-66.000,-66.000) ENVELOPE(-65.000,-65.000,-71.500,-71.500) ENVELOPE(-97.500,-97.500,-71.833,-71.833) ENVELOPE(-99.000,-99.000,-72.167,-72.167) ENVELOPE(-62.900,-62.900,-64.900,-64.900) |
geographic |
Antarctic The Antarctic Antarctic Peninsula West Antarctica Pacific Graham Land Palmer Land Thurston Thurston Island Terra Australis |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula West Antarctica Pacific Graham Land Palmer Land Thurston Thurston Island Terra Australis |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Graham Land Palmer Land Thurston Island West Antarctica |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Graham Land Palmer Land Thurston Island West Antarctica |
op_relation |
Bastias, Joaquin; Spikings, Richard; Ulianov, Alex; Riley, Teal orcid:0000-0002-3333-5021 Burton-Johnson, Alex orcid:0000-0003-2208-0075 Chiaradia, Massimo; Baumgartner, Lucas; Hervé, Francisco; Bouvier, Anne-Sophie. 2020 The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula. Gondwana Research, 81. 1-20. https://doi.org/10.1016/j.gr.2019.10.018 <https://doi.org/10.1016/j.gr.2019.10.018> |
op_doi |
https://doi.org/10.1016/j.gr.2019.10.018 |
container_title |
Gondwana Research |
container_volume |
81 |
container_start_page |
1 |
op_container_end_page |
20 |
_version_ |
1766154819136913408 |