Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia
Our current understanding of the Ellsworth Mountains stratigraphy suggests the oldest sedimentary sequence (Heritage Group) was deposited in a Cambrian rift setting. This early Paleozoic age is then used as a key piercing point to help define Cambrian paleogeography for the southern paleo-Pacific ma...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/661990 2024-05-12T07:56:23+00:00 Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia Castillo, Paula Poblete, Fernando Fernández, Rodrigo Bastías-Silva, Joaquín Fanning, C. Mark 2024-04 application/application/pdf https://hdl.handle.net/20.500.11850/661990 https://doi.org/10.3929/ethz-b-000661990 en eng Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.precamres.2024.107325 info:eu-repo/semantics/altIdentifier/wos/001187944600001 info:eu-repo/grantAgreement/SNF/Rückkehr CH Postdoc.Mobility/217947 http://hdl.handle.net/20.500.11850/661990 doi:10.3929/ethz-b-000661990 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Precambrian research, 403 Cryogenian Cambrian Zircon U-Pb O-Hf isotopes Paleo-Pacific margin Gondwana info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2024 ftethz https://doi.org/20.500.11850/66199010.3929/ethz-b-00066199010.1016/j.precamres.2024.107325 2024-04-17T14:25:36Z Our current understanding of the Ellsworth Mountains stratigraphy suggests the oldest sedimentary sequence (Heritage Group) was deposited in a Cambrian rift setting. This early Paleozoic age is then used as a key piercing point to help define Cambrian paleogeography for the southern paleo-Pacific margin of Gondwana, which places the Ellsworth Mountains between southern Africa and East Antarctica as part of West Gondwana. However, U-Pb zircon dating of a micro-diorite from the Heritage Group reveals a crystallization age of 682 ± 10 Ma, challenging chronostratigraphic and tectonic interpretations. Positive εHft and mantle-like δ18O values for these Cryogenian zircons suggest that the rifting, affecting Mesoproterozoic crust, occurred during the Cryogenian rather than in the Cambrian. This finding strongly supports a connection between the Ellsworth-Whitmore Mountain crustal block and the Transantarctic Mountains in East Antarctica prior to the amalgamation of Gondwana. It also facilitates its contextualization during the breakup of Rodinia, likely positioned close to the Shackleton Range as a continuation of the Australia-Antarctic plate, which separated from Laurentia to form the proto-Pacific Ocean in the late Neoproterozoic. This connection is supported by the U-Pb, Hf, and O data in detrital zircon grains from the lowermost units of the Heritage Group, which indicate local, East Antarctic Shield, and probable Laurentian sources. A second magmatic event in the Cambrian (516 ± 7 Ma) is recorded through zircons from a basaltic andesite within the Liberty Hills Formation, which provides an absolute depositional age for this unit. This magmatism is linked to an extensional setting, albeit distinct from that of the Cryogenian micro-diorite. The Cambrian zircons yield elevated δ18O values, indicating a strong sedimentary influence on the magma source and crustal recycling. We interpret this Cambrian extensional magmatism as a result of a tectonic escape following the collision between the East Antarctic Shield and ... Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica ETH Zürich Research Collection Antarctic East Antarctica Ellsworth Mountains ENVELOPE(-85.000,-85.000,-78.750,-78.750) Liberty Hills ENVELOPE(-82.917,-82.917,-80.100,-80.100) Pacific Shackleton Shackleton Range ENVELOPE(-26.000,-26.000,-80.833,-80.833) Transantarctic Mountains |
institution |
Open Polar |
collection |
ETH Zürich Research Collection |
op_collection_id |
ftethz |
language |
English |
topic |
Cryogenian Cambrian Zircon U-Pb O-Hf isotopes Paleo-Pacific margin Gondwana |
spellingShingle |
Cryogenian Cambrian Zircon U-Pb O-Hf isotopes Paleo-Pacific margin Gondwana Castillo, Paula Poblete, Fernando Fernández, Rodrigo Bastías-Silva, Joaquín Fanning, C. Mark Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia |
topic_facet |
Cryogenian Cambrian Zircon U-Pb O-Hf isotopes Paleo-Pacific margin Gondwana |
description |
Our current understanding of the Ellsworth Mountains stratigraphy suggests the oldest sedimentary sequence (Heritage Group) was deposited in a Cambrian rift setting. This early Paleozoic age is then used as a key piercing point to help define Cambrian paleogeography for the southern paleo-Pacific margin of Gondwana, which places the Ellsworth Mountains between southern Africa and East Antarctica as part of West Gondwana. However, U-Pb zircon dating of a micro-diorite from the Heritage Group reveals a crystallization age of 682 ± 10 Ma, challenging chronostratigraphic and tectonic interpretations. Positive εHft and mantle-like δ18O values for these Cryogenian zircons suggest that the rifting, affecting Mesoproterozoic crust, occurred during the Cryogenian rather than in the Cambrian. This finding strongly supports a connection between the Ellsworth-Whitmore Mountain crustal block and the Transantarctic Mountains in East Antarctica prior to the amalgamation of Gondwana. It also facilitates its contextualization during the breakup of Rodinia, likely positioned close to the Shackleton Range as a continuation of the Australia-Antarctic plate, which separated from Laurentia to form the proto-Pacific Ocean in the late Neoproterozoic. This connection is supported by the U-Pb, Hf, and O data in detrital zircon grains from the lowermost units of the Heritage Group, which indicate local, East Antarctic Shield, and probable Laurentian sources. A second magmatic event in the Cambrian (516 ± 7 Ma) is recorded through zircons from a basaltic andesite within the Liberty Hills Formation, which provides an absolute depositional age for this unit. This magmatism is linked to an extensional setting, albeit distinct from that of the Cryogenian micro-diorite. The Cambrian zircons yield elevated δ18O values, indicating a strong sedimentary influence on the magma source and crustal recycling. We interpret this Cambrian extensional magmatism as a result of a tectonic escape following the collision between the East Antarctic Shield and ... |
format |
Article in Journal/Newspaper |
author |
Castillo, Paula Poblete, Fernando Fernández, Rodrigo Bastías-Silva, Joaquín Fanning, C. Mark |
author_facet |
Castillo, Paula Poblete, Fernando Fernández, Rodrigo Bastías-Silva, Joaquín Fanning, C. Mark |
author_sort |
Castillo, Paula |
title |
Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia |
title_short |
Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia |
title_full |
Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia |
title_fullStr |
Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia |
title_full_unstemmed |
Re-evaluating the link between the Ellsworth Mountains and East Antarctica in the Neoproterozoic: Implications for the breakup of Rodinia and the existence of Pannotia |
title_sort |
re-evaluating the link between the ellsworth mountains and east antarctica in the neoproterozoic: implications for the breakup of rodinia and the existence of pannotia |
publisher |
Elsevier |
publishDate |
2024 |
url |
https://hdl.handle.net/20.500.11850/661990 https://doi.org/10.3929/ethz-b-000661990 |
long_lat |
ENVELOPE(-85.000,-85.000,-78.750,-78.750) ENVELOPE(-82.917,-82.917,-80.100,-80.100) ENVELOPE(-26.000,-26.000,-80.833,-80.833) |
geographic |
Antarctic East Antarctica Ellsworth Mountains Liberty Hills Pacific Shackleton Shackleton Range Transantarctic Mountains |
geographic_facet |
Antarctic East Antarctica Ellsworth Mountains Liberty Hills Pacific Shackleton Shackleton Range Transantarctic Mountains |
genre |
Antarc* Antarctic Antarctica East Antarctica |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica |
op_source |
Precambrian research, 403 |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.precamres.2024.107325 info:eu-repo/semantics/altIdentifier/wos/001187944600001 info:eu-repo/grantAgreement/SNF/Rückkehr CH Postdoc.Mobility/217947 http://hdl.handle.net/20.500.11850/661990 doi:10.3929/ethz-b-000661990 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International |
op_doi |
https://doi.org/20.500.11850/66199010.3929/ethz-b-00066199010.1016/j.precamres.2024.107325 |
_version_ |
1798836423360512000 |