Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland
We propose an intimate relationship between Silurian terrestrial red bed sedimentation (Old Red Sandstone), slab breakoff-related magmatism and deformation in the Newfoundland Appalachians. Red bed sedimentation started during the Early Silurian, and records the progressive rise of the Salinic mount...
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ftuninewbrunojs:oai:ojs.journals.lib.unb.ca:article/20466 2023-05-15T17:22:02+02:00 Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland van Staal, Cees R. Zagorevski, Alexandre McNicoll, Vicki J. Rogers, Neil 2014-05-07 application/pdf https://journals.lib.unb.ca/index.php/GC/article/view/20466 eng eng Geological Association of Canada https://journals.lib.unb.ca/index.php/GC/article/view/20466/25001 https://journals.lib.unb.ca/index.php/GC/article/view/20466 Copyright (c) 2015 Geoscience Canada Geoscience Canada; Volume 41, Number 2 (2014); 138-164 1911-4850 0315-0941 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2014 ftuninewbrunojs 2022-07-11T11:48:25Z We propose an intimate relationship between Silurian terrestrial red bed sedimentation (Old Red Sandstone), slab breakoff-related magmatism and deformation in the Newfoundland Appalachians. Red bed sedimentation started during the Early Silurian, and records the progressive rise of the Salinic mountains in the tectonic hinterland of the orogen. The red beds were mainly deposited in molasse-style foreland basins in front of an east-propagating terminal Salinic deformation front. New U–Pb zircon dating of volcanic rocks interlayered with the Silurian red beds in key structural locations yielded ages ranging between 425 and 418 Ma, which, combined with the existing geochronological database, suggests that the sedimentary rocks are progressively younger from west to east and overstep the accreted Gondwana-derived terranes. We propose that deposition of the red beds is a good proxy for the time of cratonization of the accreted terranes. Eastward migration of the Salinic deformation front was accompanied by eastward-widening of a slab-breakoff-related asthenospheric window. The latter is interpreted to have formed due to a combination of progressive steepening of the down-going plate following entrance of the leading edge of the Gander margin and its eduction. Gander margin eduction (reversed subduction) is proposed to have been instigated by the trench migration of the Acadian coastal arc built upon the trailing edge of the Gander margin, which developed contemporaneously with the Salinic collision. The resultant thinning of the lithosphere beneath the Salinic orogen, built upon the leading edge of the Gander margin immediately prior to the onset of the Early Devonian Acadian orogeny, set the stage for generation of the widespread bloom of Acadian magmatism.SOMMAIRENous proposons qu’il y a eu une relation intime entre la sédimentation des couches rouges continentales au Silurien (vieux-grès-rouges), un magmatisme lié à une rupture de segments de croûte, et la déformation appalachienne à Terre-Neuve. La sédimentation ... Article in Journal/Newspaper Newfoundland Terre-Neuve University of New Brunswick: Centre for Digital Scholarship Journals Geoscience Canada 41 2 138 |
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We propose an intimate relationship between Silurian terrestrial red bed sedimentation (Old Red Sandstone), slab breakoff-related magmatism and deformation in the Newfoundland Appalachians. Red bed sedimentation started during the Early Silurian, and records the progressive rise of the Salinic mountains in the tectonic hinterland of the orogen. The red beds were mainly deposited in molasse-style foreland basins in front of an east-propagating terminal Salinic deformation front. New U–Pb zircon dating of volcanic rocks interlayered with the Silurian red beds in key structural locations yielded ages ranging between 425 and 418 Ma, which, combined with the existing geochronological database, suggests that the sedimentary rocks are progressively younger from west to east and overstep the accreted Gondwana-derived terranes. We propose that deposition of the red beds is a good proxy for the time of cratonization of the accreted terranes. Eastward migration of the Salinic deformation front was accompanied by eastward-widening of a slab-breakoff-related asthenospheric window. The latter is interpreted to have formed due to a combination of progressive steepening of the down-going plate following entrance of the leading edge of the Gander margin and its eduction. Gander margin eduction (reversed subduction) is proposed to have been instigated by the trench migration of the Acadian coastal arc built upon the trailing edge of the Gander margin, which developed contemporaneously with the Salinic collision. The resultant thinning of the lithosphere beneath the Salinic orogen, built upon the leading edge of the Gander margin immediately prior to the onset of the Early Devonian Acadian orogeny, set the stage for generation of the widespread bloom of Acadian magmatism.SOMMAIRENous proposons qu’il y a eu une relation intime entre la sédimentation des couches rouges continentales au Silurien (vieux-grès-rouges), un magmatisme lié à une rupture de segments de croûte, et la déformation appalachienne à Terre-Neuve. La sédimentation ... |
format |
Article in Journal/Newspaper |
author |
van Staal, Cees R. Zagorevski, Alexandre McNicoll, Vicki J. Rogers, Neil |
spellingShingle |
van Staal, Cees R. Zagorevski, Alexandre McNicoll, Vicki J. Rogers, Neil Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland |
author_facet |
van Staal, Cees R. Zagorevski, Alexandre McNicoll, Vicki J. Rogers, Neil |
author_sort |
van Staal, Cees R. |
title |
Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland |
title_short |
Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland |
title_full |
Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland |
title_fullStr |
Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland |
title_full_unstemmed |
Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland |
title_sort |
time-transgressive salinic and acadian orogenesis, magmatism and old red sandstone sedimentation in newfoundland |
publisher |
Geological Association of Canada |
publishDate |
2014 |
url |
https://journals.lib.unb.ca/index.php/GC/article/view/20466 |
genre |
Newfoundland Terre-Neuve |
genre_facet |
Newfoundland Terre-Neuve |
op_source |
Geoscience Canada; Volume 41, Number 2 (2014); 138-164 1911-4850 0315-0941 |
op_relation |
https://journals.lib.unb.ca/index.php/GC/article/view/20466/25001 https://journals.lib.unb.ca/index.php/GC/article/view/20466 |
op_rights |
Copyright (c) 2015 Geoscience Canada |
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