Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada)
A new model for evolution of the Archean Hopedale Block, based on mapping and supporting UPb geochronological and geochemical studies, is highlighted by (i) ca. 3.25 Ga emplacement of igneous precursors of Maggo Gneiss; (ii) >3.1 Ga, high-grade Hopedalian metamorphism and attendant deformatio...
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crcansciencepubl:10.1139/e01-092 2024-04-07T07:54:34+00:00 Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada) James, D T Kamo, S Krogh, T 2002 http://dx.doi.org/10.1139/e01-092 http://www.nrcresearchpress.com/doi/pdf/10.1139/e01-092 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 39, issue 5, page 687-710 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 2002 crcansciencepubl https://doi.org/10.1139/e01-092 2024-03-08T00:37:49Z A new model for evolution of the Archean Hopedale Block, based on mapping and supporting UPb geochronological and geochemical studies, is highlighted by (i) ca. 3.25 Ga emplacement of igneous precursors of Maggo Gneiss; (ii) >3.1 Ga, high-grade Hopedalian metamorphism and attendant deformation; (iii) emplacement of the Hopedale mafic dykes; (iv) 3.1 Ga deposition of Hunt River volcanic rocks; (v) ca. 3.0 Ga deposition of Florence Lake volcanic rocks; (vi) 2.882.96 Ga, greenschist- to amphibolite-facies Fiordian metamorphism and formation of penetrative, northeast-striking Fiordian structures; and (vii) emplacement of a suite of 2.892.83 Ga tonalite to granite intrusions, which partially overlap and locally postdate Fiordian metamorphism and deformation. The Hunt River and Florence Lake volcanic sequences are different in age but similar in most other respects. The former consists mainly of amphibolite-facies mafic metavolcanic rocks and lesser amounts of komatiite flows and metasedimentary and 3105 ± 3 Ma felsic volcanic rocks. The Florence Lake volcanic belt consists mainly of greenschist- to amphibolite-facies mafic metavolcanic rocks, lesser amounts of felsic metavolcanic rocks, dated at 2979 ± 1 and 2990 ± 2 Ma, komatiite flows, and rare metasedimentary rocks. The similarity of rock types, field relationships between different rock types, such as the common association of ultramafic and felsic metavolcanic rocks, and the chemistry of volcanic rocks in both belts suggest a common tectonic setting for each belt. A model involving episodic volcanism, separated by 100 Ma, in ensialic basins is consistent with the dominance of tholeiitic basalt and an abundance of pre-volcanic basement. Article in Journal/Newspaper North Atlantic Canadian Science Publishing Canada Canadian Journal of Earth Sciences 39 5 687 710 |
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Open Polar |
collection |
Canadian Science Publishing |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences James, D T Kamo, S Krogh, T Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada) |
topic_facet |
General Earth and Planetary Sciences |
description |
A new model for evolution of the Archean Hopedale Block, based on mapping and supporting UPb geochronological and geochemical studies, is highlighted by (i) ca. 3.25 Ga emplacement of igneous precursors of Maggo Gneiss; (ii) >3.1 Ga, high-grade Hopedalian metamorphism and attendant deformation; (iii) emplacement of the Hopedale mafic dykes; (iv) 3.1 Ga deposition of Hunt River volcanic rocks; (v) ca. 3.0 Ga deposition of Florence Lake volcanic rocks; (vi) 2.882.96 Ga, greenschist- to amphibolite-facies Fiordian metamorphism and formation of penetrative, northeast-striking Fiordian structures; and (vii) emplacement of a suite of 2.892.83 Ga tonalite to granite intrusions, which partially overlap and locally postdate Fiordian metamorphism and deformation. The Hunt River and Florence Lake volcanic sequences are different in age but similar in most other respects. The former consists mainly of amphibolite-facies mafic metavolcanic rocks and lesser amounts of komatiite flows and metasedimentary and 3105 ± 3 Ma felsic volcanic rocks. The Florence Lake volcanic belt consists mainly of greenschist- to amphibolite-facies mafic metavolcanic rocks, lesser amounts of felsic metavolcanic rocks, dated at 2979 ± 1 and 2990 ± 2 Ma, komatiite flows, and rare metasedimentary rocks. The similarity of rock types, field relationships between different rock types, such as the common association of ultramafic and felsic metavolcanic rocks, and the chemistry of volcanic rocks in both belts suggest a common tectonic setting for each belt. A model involving episodic volcanism, separated by 100 Ma, in ensialic basins is consistent with the dominance of tholeiitic basalt and an abundance of pre-volcanic basement. |
format |
Article in Journal/Newspaper |
author |
James, D T Kamo, S Krogh, T |
author_facet |
James, D T Kamo, S Krogh, T |
author_sort |
James, D T |
title |
Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada) |
title_short |
Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada) |
title_full |
Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada) |
title_fullStr |
Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada) |
title_full_unstemmed |
Evolution of 3.1 and 3.0 Ga volcanic belts and a new thermotectonic model for the Hopedale Block, North Atlantic craton (Canada) |
title_sort |
evolution of 3.1 and 3.0 ga volcanic belts and a new thermotectonic model for the hopedale block, north atlantic craton (canada) |
publisher |
Canadian Science Publishing |
publishDate |
2002 |
url |
http://dx.doi.org/10.1139/e01-092 http://www.nrcresearchpress.com/doi/pdf/10.1139/e01-092 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Canadian Journal of Earth Sciences volume 39, issue 5, page 687-710 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e01-092 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
39 |
container_issue |
5 |
container_start_page |
687 |
op_container_end_page |
710 |
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1795671195613396992 |