Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen
Northern Victoria Land, Antarctica, plays a key role in any geodynamic reconstructions of the paleo-Pacific margin of Gondwana because it represents the along-strike continuation of Australia in Antarctica and hosts the only Paleozoic eclogites known along the Transantarctic Mountains. The architect...
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ftcaltechauth:oai:authors.library.caltech.edu:ty33v-jkr28 2024-06-23T07:46:02+00:00 Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen Di Vincenzo, Gianfranco Horton, Forrest Palmeri, Rosaria 2016-12 https://doi.org/10.1016/j.gr.2016.08.005 unknown Elsevier https://doi.org/10.1016/j.gr.2016.08.005 oai:authors.library.caltech.edu:ty33v-jkr28 eprintid:76595 resolverid:CaltechAUTHORS:20170417-105459245 info:eu-repo/semantics/closedAccess Other Gondwana Research, 40, 91-106, (2016-12) Antarctica Eclogite-facies metamorphism Northern Victoria Land Ross Orogen Split-stream LA-ICP-MS Zircon info:eu-repo/semantics/article 2016 ftcaltechauth https://doi.org/10.1016/j.gr.2016.08.005 2024-06-12T06:27:06Z Northern Victoria Land, Antarctica, plays a key role in any geodynamic reconstructions of the paleo-Pacific margin of Gondwana because it represents the along-strike continuation of Australia in Antarctica and hosts the only Paleozoic eclogites known along the Transantarctic Mountains. The architecture and evolution of the early Cambrian to Early Ordovician Ross–Delamerian Orogen in northern Victoria Land, however, remain controversial. Accurate geodynamic reconstructions have been hindered by a dearth of temporal metamorphic constraints. This study reports laser-ablation split-stream ICP-MS data on zircon in newly recognized eclogite, that preserves a memory of the prograde evolution, and on zircon from its country rock from the Lanterman Range of northern Victoria Land. Geochronological data are supplemented for the eclogite by whole-rock geochemical and petrological constraints, that indicate an E-MORB protolith derived from a depleted mantle source, and P–T conditions for the eclogite-facies stage of ~ 700 °C and 1.7–2.4 GPa. U–Pb ages, trace-element contents, cathodoluminescence imaging and textural/inclusion relationships testify to protracted zircon growth/recrystallization history under eclogite-facies conditions, that also included (re)crystallization during part of the prograde path. Results extend the onset of eclogite-facies metamorphism in northern Victoria Land back to ~ 530 Ma and, together with geochronological evidence for the emplacement of calc-alkaline granitoids at ~ 530–520 Ma, suggest that UHP–HP rocks formed by accretion of material beneath an active continental margin. Regionally, this interpretation implies that burial of mafic rocks and associated siliciclastic sequences to mantle depths commenced significantly earlier than previously believed (~ 500 Ma), thereby contrasting with the common belief that high-pressure metamorphism was linked to arc–continent collision. New and old results reveal the coexistence along the same ridge of two eclogite types: (1) ... Article in Journal/Newspaper Antarc* Antarctica Victoria Land Caltech Authors (California Institute of Technology) Lanterman Range ENVELOPE(163.167,163.167,-71.667,-71.667) Pacific Transantarctic Mountains Victoria Land Gondwana Research 40 91 106 |
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Open Polar |
collection |
Caltech Authors (California Institute of Technology) |
op_collection_id |
ftcaltechauth |
language |
unknown |
topic |
Antarctica Eclogite-facies metamorphism Northern Victoria Land Ross Orogen Split-stream LA-ICP-MS Zircon |
spellingShingle |
Antarctica Eclogite-facies metamorphism Northern Victoria Land Ross Orogen Split-stream LA-ICP-MS Zircon Di Vincenzo, Gianfranco Horton, Forrest Palmeri, Rosaria Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen |
topic_facet |
Antarctica Eclogite-facies metamorphism Northern Victoria Land Ross Orogen Split-stream LA-ICP-MS Zircon |
description |
Northern Victoria Land, Antarctica, plays a key role in any geodynamic reconstructions of the paleo-Pacific margin of Gondwana because it represents the along-strike continuation of Australia in Antarctica and hosts the only Paleozoic eclogites known along the Transantarctic Mountains. The architecture and evolution of the early Cambrian to Early Ordovician Ross–Delamerian Orogen in northern Victoria Land, however, remain controversial. Accurate geodynamic reconstructions have been hindered by a dearth of temporal metamorphic constraints. This study reports laser-ablation split-stream ICP-MS data on zircon in newly recognized eclogite, that preserves a memory of the prograde evolution, and on zircon from its country rock from the Lanterman Range of northern Victoria Land. Geochronological data are supplemented for the eclogite by whole-rock geochemical and petrological constraints, that indicate an E-MORB protolith derived from a depleted mantle source, and P–T conditions for the eclogite-facies stage of ~ 700 °C and 1.7–2.4 GPa. U–Pb ages, trace-element contents, cathodoluminescence imaging and textural/inclusion relationships testify to protracted zircon growth/recrystallization history under eclogite-facies conditions, that also included (re)crystallization during part of the prograde path. Results extend the onset of eclogite-facies metamorphism in northern Victoria Land back to ~ 530 Ma and, together with geochronological evidence for the emplacement of calc-alkaline granitoids at ~ 530–520 Ma, suggest that UHP–HP rocks formed by accretion of material beneath an active continental margin. Regionally, this interpretation implies that burial of mafic rocks and associated siliciclastic sequences to mantle depths commenced significantly earlier than previously believed (~ 500 Ma), thereby contrasting with the common belief that high-pressure metamorphism was linked to arc–continent collision. New and old results reveal the coexistence along the same ridge of two eclogite types: (1) ... |
format |
Article in Journal/Newspaper |
author |
Di Vincenzo, Gianfranco Horton, Forrest Palmeri, Rosaria |
author_facet |
Di Vincenzo, Gianfranco Horton, Forrest Palmeri, Rosaria |
author_sort |
Di Vincenzo, Gianfranco |
title |
Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen |
title_short |
Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen |
title_full |
Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen |
title_fullStr |
Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen |
title_full_unstemmed |
Protracted (~30Ma) eclogite-facies metamorphism in northern Victoria Land (Antarctica): Implications for the geodynamics of the Ross/Delamerian Orogen |
title_sort |
protracted (~30ma) eclogite-facies metamorphism in northern victoria land (antarctica): implications for the geodynamics of the ross/delamerian orogen |
publisher |
Elsevier |
publishDate |
2016 |
url |
https://doi.org/10.1016/j.gr.2016.08.005 |
long_lat |
ENVELOPE(163.167,163.167,-71.667,-71.667) |
geographic |
Lanterman Range Pacific Transantarctic Mountains Victoria Land |
geographic_facet |
Lanterman Range Pacific Transantarctic Mountains Victoria Land |
genre |
Antarc* Antarctica Victoria Land |
genre_facet |
Antarc* Antarctica Victoria Land |
op_source |
Gondwana Research, 40, 91-106, (2016-12) |
op_relation |
https://doi.org/10.1016/j.gr.2016.08.005 oai:authors.library.caltech.edu:ty33v-jkr28 eprintid:76595 resolverid:CaltechAUTHORS:20170417-105459245 |
op_rights |
info:eu-repo/semantics/closedAccess Other |
op_doi |
https://doi.org/10.1016/j.gr.2016.08.005 |
container_title |
Gondwana Research |
container_volume |
40 |
container_start_page |
91 |
op_container_end_page |
106 |
_version_ |
1802643582267424768 |