Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada
Abstract Dating the onset of continental collision is fundamental in defining orogenic cycles and their effects on regional tectonics and geodynamic processes through time. Part of the Palaeoproterozoic Trans‐Hudson Orogen, the Southeastern Churchill Province (SECP) is interpreted to result from the...
Published in: | Journal of Metamorphic Geology |
---|---|
Main Authors: | , , , , , , |
Other Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
2021
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1111/jmg.12599 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jmg.12599 https://onlinelibrary.wiley.com/doi/full-xml/10.1111/jmg.12599 |
id |
crwiley:10.1111/jmg.12599 |
---|---|
record_format |
openpolar |
spelling |
crwiley:10.1111/jmg.12599 2024-06-23T07:55:05+00:00 Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada Godet, Antoine Guilmette, Carl Labrousse, Loic Smit, Matthijs A. Cutts, Jamie A. Davis, Donald W. Vanier, Marc‐Antoine Ministère de l'Énergie et des Ressources Naturelles Canadian Network for Research and Innovation in Machining Technology, Natural Sciences and Engineering Research Council of Canada British Columbia Knowledge Development Fund 2021 http://dx.doi.org/10.1111/jmg.12599 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jmg.12599 https://onlinelibrary.wiley.com/doi/full-xml/10.1111/jmg.12599 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Metamorphic Geology volume 39, issue 8, page 977-1007 ISSN 0263-4929 1525-1314 journal-article 2021 crwiley https://doi.org/10.1111/jmg.12599 2024-06-06T04:22:02Z Abstract Dating the onset of continental collision is fundamental in defining orogenic cycles and their effects on regional tectonics and geodynamic processes through time. Part of the Palaeoproterozoic Trans‐Hudson Orogen, the Southeastern Churchill Province (SECP) is interpreted to result from the amalgamation of Archean to Palaeoproterozoic crustal blocks (amalgamated as the central Core Zone) that diachronically collided with the margins of the North Atlantic and Superior cratons, resulting in two bounding transpressive orogens: the Torngat and New Quebec Orogens. The SECP exposes mainly gneissic middle to lower orogenic crust in which deformation and amphibolite to granulite facies metamorphism and anatexis overprinted the early geological features classically used to constrain the timing of collisional events. To enable improved tectonic models for the development of the SECP, and the Trans‐Hudson as a whole, we investigated granulite facies supracrustal sequences from the Tasiuyak Complex (TC) accretionary prism and the western margin of the North Atlantic Craton—that is, Saglek Block (upper plate)—using a multi‐chronometer approach coupled with trace element geochemistry. In particular, the use of garnet Lu–Hf geochronology provides an important minimal time constraint for crustal thickening and collision. Garnet growth in the TC is constrained at 1885 ± 12 Ma (Lu–Hf), indistinguishable from U–Pb age of prograde monazite at 1873 ± 5 Ma. Zircon growth during melt crystallization occurred at 1848 ± 12 Ma. Garnet from the overriding Saglek Block is dated at 2567 ± 4.4 Ma (Lu–Hf) and indicates that gneissic rocks from the upper plate did not record the metamorphic imprint of the Torngat Orogeny. The diachronicity of the integrated metamorphic record across the strike of the SECP is explained by the location of terrane boundaries, consistent with the westward growth of the Churchill plate margin through sequential amalgamation of narrow crustal blocks during accretionary tectonics from c . 1.9 to 1.8 Ga. Article in Journal/Newspaper North Atlantic Wiley Online Library Canada Hudson Journal of Metamorphic Geology 39 8 977 1007 |
institution |
Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
Abstract Dating the onset of continental collision is fundamental in defining orogenic cycles and their effects on regional tectonics and geodynamic processes through time. Part of the Palaeoproterozoic Trans‐Hudson Orogen, the Southeastern Churchill Province (SECP) is interpreted to result from the amalgamation of Archean to Palaeoproterozoic crustal blocks (amalgamated as the central Core Zone) that diachronically collided with the margins of the North Atlantic and Superior cratons, resulting in two bounding transpressive orogens: the Torngat and New Quebec Orogens. The SECP exposes mainly gneissic middle to lower orogenic crust in which deformation and amphibolite to granulite facies metamorphism and anatexis overprinted the early geological features classically used to constrain the timing of collisional events. To enable improved tectonic models for the development of the SECP, and the Trans‐Hudson as a whole, we investigated granulite facies supracrustal sequences from the Tasiuyak Complex (TC) accretionary prism and the western margin of the North Atlantic Craton—that is, Saglek Block (upper plate)—using a multi‐chronometer approach coupled with trace element geochemistry. In particular, the use of garnet Lu–Hf geochronology provides an important minimal time constraint for crustal thickening and collision. Garnet growth in the TC is constrained at 1885 ± 12 Ma (Lu–Hf), indistinguishable from U–Pb age of prograde monazite at 1873 ± 5 Ma. Zircon growth during melt crystallization occurred at 1848 ± 12 Ma. Garnet from the overriding Saglek Block is dated at 2567 ± 4.4 Ma (Lu–Hf) and indicates that gneissic rocks from the upper plate did not record the metamorphic imprint of the Torngat Orogeny. The diachronicity of the integrated metamorphic record across the strike of the SECP is explained by the location of terrane boundaries, consistent with the westward growth of the Churchill plate margin through sequential amalgamation of narrow crustal blocks during accretionary tectonics from c . 1.9 to 1.8 Ga. |
author2 |
Ministère de l'Énergie et des Ressources Naturelles Canadian Network for Research and Innovation in Machining Technology, Natural Sciences and Engineering Research Council of Canada British Columbia Knowledge Development Fund |
format |
Article in Journal/Newspaper |
author |
Godet, Antoine Guilmette, Carl Labrousse, Loic Smit, Matthijs A. Cutts, Jamie A. Davis, Donald W. Vanier, Marc‐Antoine |
spellingShingle |
Godet, Antoine Guilmette, Carl Labrousse, Loic Smit, Matthijs A. Cutts, Jamie A. Davis, Donald W. Vanier, Marc‐Antoine Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada |
author_facet |
Godet, Antoine Guilmette, Carl Labrousse, Loic Smit, Matthijs A. Cutts, Jamie A. Davis, Donald W. Vanier, Marc‐Antoine |
author_sort |
Godet, Antoine |
title |
Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada |
title_short |
Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada |
title_full |
Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada |
title_fullStr |
Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada |
title_full_unstemmed |
Lu–Hf garnet dating and the timing of collisions: Palaeoproterozoic accretionary tectonics revealed in the Southeastern Churchill Province, Trans‐Hudson Orogen, Canada |
title_sort |
lu–hf garnet dating and the timing of collisions: palaeoproterozoic accretionary tectonics revealed in the southeastern churchill province, trans‐hudson orogen, canada |
publisher |
Wiley |
publishDate |
2021 |
url |
http://dx.doi.org/10.1111/jmg.12599 https://onlinelibrary.wiley.com/doi/pdf/10.1111/jmg.12599 https://onlinelibrary.wiley.com/doi/full-xml/10.1111/jmg.12599 |
geographic |
Canada Hudson |
geographic_facet |
Canada Hudson |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Journal of Metamorphic Geology volume 39, issue 8, page 977-1007 ISSN 0263-4929 1525-1314 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1111/jmg.12599 |
container_title |
Journal of Metamorphic Geology |
container_volume |
39 |
container_issue |
8 |
container_start_page |
977 |
op_container_end_page |
1007 |
_version_ |
1802647491910303744 |