Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada
Upper Cambrian to Middle Ordovician mafic volcanic rocks of the Donjek assemblage comprise the oldest exposed units of the Alexander terrane in the Saint Elias Mountains of northwestern Canada. In this study, we use the geochemical and geological characteristics of these rocks to decipher their tect...
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University of Chicago Press
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ftunivtasecite:oai:ecite.utas.edu.au:82544 2023-05-15T15:07:49+02:00 Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada Beranek, LP van Staal, CR Gordee, Sarah M McClelland, WC Israel, S Mihalynuk, M 2012 application/pdf https://doi.org/10.1086/664788 http://ecite.utas.edu.au/82544 en eng University of Chicago Press http://ecite.utas.edu.au/82544/1/Gordee-JGeol.pdf http://dx.doi.org/10.1086/664788 Beranek, LP and van Staal, CR and Gordee, Sarah M and McClelland, WC and Israel, S and Mihalynuk, M, Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada, Journal of Geology, 120, (3) pp. 293-314. ISSN 0022-1376 (2012) [Refereed Article] http://ecite.utas.edu.au/82544 Earth Sciences Geology Tectonics Refereed Article PeerReviewed 2012 ftunivtasecite https://doi.org/10.1086/664788 2019-12-13T21:47:22Z Upper Cambrian to Middle Ordovician mafic volcanic rocks of the Donjek assemblage comprise the oldest exposed units of the Alexander terrane in the Saint Elias Mountains of northwestern Canada. In this study, we use the geochemical and geological characteristics of these rocks to decipher their tectonic setting, petrogenetic history, and relationship to the early Paleozoic Descon arc system of the Alexander terrane in southeastern Alaska. Donjek assemblage volcanic rocks are subdivided into three geochemical types: transitional basalt (type I), light rare earth enriched island-arc tholeiite to calc-alkaline basalt (type II), and enriched mid-ocean ridge basalt to ocean-island basalt (type III). Simple petrogenetic models illustrate that the basalts were generated by the decompressional partial melting of enriched asthenospheric mantle and variably mixed with depleted mantle and subduction-related components. Analogous geochemical signatures for modern Sumisu Rift and Okinawa Trough lavas imply that the Donjek assemblage basalts erupted during the rifting of the Descon arc. This model provides a new comparative framework for terranes of Siberian, Baltican, and Caledonian affinity in the North American Cordillera and, in particular, suggests a paleogeographic connection to rift-related magmatism in the Seward Peninsula region of the Arctic AlaskaChukotka terrane. Article in Journal/Newspaper Arctic Seward Peninsula Alaska Ocean Island eCite UTAS (University of Tasmania) Arctic Canada The Journal of Geology 120 3 293 314 |
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Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Geology Tectonics |
spellingShingle |
Earth Sciences Geology Tectonics Beranek, LP van Staal, CR Gordee, Sarah M McClelland, WC Israel, S Mihalynuk, M Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada |
topic_facet |
Earth Sciences Geology Tectonics |
description |
Upper Cambrian to Middle Ordovician mafic volcanic rocks of the Donjek assemblage comprise the oldest exposed units of the Alexander terrane in the Saint Elias Mountains of northwestern Canada. In this study, we use the geochemical and geological characteristics of these rocks to decipher their tectonic setting, petrogenetic history, and relationship to the early Paleozoic Descon arc system of the Alexander terrane in southeastern Alaska. Donjek assemblage volcanic rocks are subdivided into three geochemical types: transitional basalt (type I), light rare earth enriched island-arc tholeiite to calc-alkaline basalt (type II), and enriched mid-ocean ridge basalt to ocean-island basalt (type III). Simple petrogenetic models illustrate that the basalts were generated by the decompressional partial melting of enriched asthenospheric mantle and variably mixed with depleted mantle and subduction-related components. Analogous geochemical signatures for modern Sumisu Rift and Okinawa Trough lavas imply that the Donjek assemblage basalts erupted during the rifting of the Descon arc. This model provides a new comparative framework for terranes of Siberian, Baltican, and Caledonian affinity in the North American Cordillera and, in particular, suggests a paleogeographic connection to rift-related magmatism in the Seward Peninsula region of the Arctic AlaskaChukotka terrane. |
format |
Article in Journal/Newspaper |
author |
Beranek, LP van Staal, CR Gordee, Sarah M McClelland, WC Israel, S Mihalynuk, M |
author_facet |
Beranek, LP van Staal, CR Gordee, Sarah M McClelland, WC Israel, S Mihalynuk, M |
author_sort |
Beranek, LP |
title |
Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada |
title_short |
Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada |
title_full |
Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada |
title_fullStr |
Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada |
title_full_unstemmed |
Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada |
title_sort |
tectonic significance of upper cambrian-middle ordovician mafic volcanic rocks on the alexander terrane, saint elias mountains, northwestern canada |
publisher |
University of Chicago Press |
publishDate |
2012 |
url |
https://doi.org/10.1086/664788 http://ecite.utas.edu.au/82544 |
geographic |
Arctic Canada |
geographic_facet |
Arctic Canada |
genre |
Arctic Seward Peninsula Alaska Ocean Island |
genre_facet |
Arctic Seward Peninsula Alaska Ocean Island |
op_relation |
http://ecite.utas.edu.au/82544/1/Gordee-JGeol.pdf http://dx.doi.org/10.1086/664788 Beranek, LP and van Staal, CR and Gordee, Sarah M and McClelland, WC and Israel, S and Mihalynuk, M, Tectonic significance of Upper Cambrian-Middle Ordovician Mafic volcanic rocks on the Alexander Terrane, Saint Elias Mountains, Northwestern Canada, Journal of Geology, 120, (3) pp. 293-314. ISSN 0022-1376 (2012) [Refereed Article] http://ecite.utas.edu.au/82544 |
op_doi |
https://doi.org/10.1086/664788 |
container_title |
The Journal of Geology |
container_volume |
120 |
container_issue |
3 |
container_start_page |
293 |
op_container_end_page |
314 |
_version_ |
1766339245798064128 |