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...
Published in: | Gondwana Research |
---|---|
Main Authors: | , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Elsevier
2020
|
Subjects: | |
Online Access: | https://doi.org/10.1016/j.gr.2019.10.018 https://repositorio.uchile.cl/handle/2250/175048 |
id |
ftunivchile:oai:repositorio.uchile.cl:2250/175048 |
---|---|
record_format |
openpolar |
spelling |
ftunivchile:oai:repositorio.uchile.cl:2250/175048 2023-05-15T13:34:34+02:00 The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula Bastías, Joaquín Spikings, Richard Ulianov, Alex Riley, Teal Burton Johnson, Alex Chiaradia, Massimo Baumgartner, Lukas Hervé Allamand, Francisco Bouvier, Anne-Sophie 2020 application/pdf https://doi.org/10.1016/j.gr.2019.10.018 https://repositorio.uchile.cl/handle/2250/175048 en eng Elsevier Gondwana Research 81 (2020) 1–20 doi:10.1016/j.gr.2019.10.018 https://repositorio.uchile.cl/handle/2250/175048 Attribution-NonCommercial-NoDerivs 3.0 Chile http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ CC-BY-NC-ND Gondwana Research Zircon U-Pb Eastern Palmer Land Rare-earth-elements I-type granites Lu-Hf Break-up Tectonic evolution Trace-element South-America Graham land Artículo de revista 2020 ftunivchile https://doi.org/10.1016/j.gr.2019.10.018 2022-12-25T00:51:28Z 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-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, talc-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 Sunsasand Brazilian-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 aulochthonous to Gondwana. Chilean Antarctic Institute: RT-06-14. University of Geneva. CONICYT -Chile scholarship. Earth Science Department of the University of Geneva. ... Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Graham Land Palmer Land Thurston Island West Antarctica Universidad de Chile: Repositorio académico Antarctic Antarctic Peninsula Graham Land ENVELOPE(-63.500,-63.500,-66.000,-66.000) Pacific Palmer Land ENVELOPE(-65.000,-65.000,-71.500,-71.500) Terra Australis ENVELOPE(-62.900,-62.900,-64.900,-64.900) The Antarctic Thurston ENVELOPE(-97.500,-97.500,-71.833,-71.833) Thurston Island ENVELOPE(-99.000,-99.000,-72.167,-72.167) West Antarctica Gondwana Research 81 1 20 |
institution |
Open Polar |
collection |
Universidad de Chile: Repositorio académico |
op_collection_id |
ftunivchile |
language |
English |
topic |
Zircon U-Pb Eastern Palmer Land Rare-earth-elements I-type granites Lu-Hf Break-up Tectonic evolution Trace-element South-America Graham land |
spellingShingle |
Zircon U-Pb Eastern Palmer Land Rare-earth-elements I-type granites Lu-Hf Break-up Tectonic evolution Trace-element South-America Graham land Bastías, Joaquín Spikings, Richard Ulianov, Alex Riley, Teal Burton Johnson, Alex Chiaradia, Massimo Baumgartner, Lukas Hervé Allamand, Francisco Bouvier, Anne-Sophie The Gondwanan margin in West Antarctica: insights from Late Triassic magmatism of the Antarctic Peninsula |
topic_facet |
Zircon U-Pb Eastern Palmer Land Rare-earth-elements I-type granites Lu-Hf Break-up Tectonic evolution Trace-element South-America Graham land |
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-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, talc-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 Sunsasand Brazilian-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 aulochthonous to Gondwana. Chilean Antarctic Institute: RT-06-14. University of Geneva. CONICYT -Chile scholarship. Earth Science Department of the University of Geneva. ... |
format |
Article in Journal/Newspaper |
author |
Bastías, Joaquín Spikings, Richard Ulianov, Alex Riley, Teal Burton Johnson, Alex Chiaradia, Massimo Baumgartner, Lukas Hervé Allamand, Francisco Bouvier, Anne-Sophie |
author_facet |
Bastías, Joaquín Spikings, Richard Ulianov, Alex Riley, Teal Burton Johnson, Alex Chiaradia, Massimo Baumgartner, Lukas Hervé Allamand, Francisco Bouvier, Anne-Sophie |
author_sort |
Bastías, Joaquín |
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 |
https://doi.org/10.1016/j.gr.2019.10.018 https://repositorio.uchile.cl/handle/2250/175048 |
long_lat |
ENVELOPE(-63.500,-63.500,-66.000,-66.000) ENVELOPE(-65.000,-65.000,-71.500,-71.500) ENVELOPE(-62.900,-62.900,-64.900,-64.900) ENVELOPE(-97.500,-97.500,-71.833,-71.833) ENVELOPE(-99.000,-99.000,-72.167,-72.167) |
geographic |
Antarctic Antarctic Peninsula Graham Land Pacific Palmer Land Terra Australis The Antarctic Thurston Thurston Island West Antarctica |
geographic_facet |
Antarctic Antarctic Peninsula Graham Land Pacific Palmer Land Terra Australis The Antarctic Thurston Thurston Island West Antarctica |
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_source |
Gondwana Research |
op_relation |
Gondwana Research 81 (2020) 1–20 doi:10.1016/j.gr.2019.10.018 https://repositorio.uchile.cl/handle/2250/175048 |
op_rights |
Attribution-NonCommercial-NoDerivs 3.0 Chile http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ |
op_rightsnorm |
CC-BY-NC-ND |
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_ |
1766054412574261248 |