Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence
Allochthons in the Cassiar Mountains of northern British Columbia contain assemblages belonging to two distinct Canadian Cordilleran terranes, YukonTanana (YTT) and Quesnellia. These assemblages, of pre-Late Devonian, DevonianMississippian, PennsylvanianPermian, and Early Jurassic age, occur in i...
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crcansciencepubl:10.1139/e04-028 2024-04-28T08:41:39+00:00 Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence Nelson, JoAnne Friedman, Richard 2004 http://dx.doi.org/10.1139/e04-028 http://www.nrcresearchpress.com/doi/pdf/10.1139/e04-028 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 41, issue 10, page 1201-1235 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 2004 crcansciencepubl https://doi.org/10.1139/e04-028 2024-04-02T06:55:56Z Allochthons in the Cassiar Mountains of northern British Columbia contain assemblages belonging to two distinct Canadian Cordilleran terranes, YukonTanana (YTT) and Quesnellia. These assemblages, of pre-Late Devonian, DevonianMississippian, PennsylvanianPermian, and Early Jurassic age, occur in intrusive and depositional, as well as structural, contact with each other. The allochthons are gently dipping thrust panels, interrupted by the mid-Cretaceous Cassiar Batholith. A key element for correlation across the batholith is the Mississippian and older pericratonic Dorsey Complex. New DevonianMississippian UPb ages for deformed plutons within it document an igneous suite like those in type YukonTanana exposures farther north. Other characteristics of the Dorsey Complex that ally it with YTT are orthoquartzites and grits, and amphibolite bodies with transitional mid-ocean ridge basalt (MORB) to ocean-island basalt (OIB) petrochemical signatures. Unconformities, deformed clasts in the late Paleozoic sequences, and a shared mid-Permian intrusive suite show that later arcs onlapped the mid-Paleozoic and older YTT assemblage. The Early Jurassic intrusive suite cuts all major contacts and fabrics except the terrane-bounding fault between the Slide Mountain and combined YTTQuesnel terranes. It represents a northern continuation of a plutonic belt that extends the length of the Mesozoic Quesnel magmatic arc. These relationships carry important implications for Cordilleran terrane history and the tectonic evolution of the North American margin. At least some of the major terranes were not unrelated entities prior to their accretion to the continent, but a system of superimposed and interconnected arcs that developed over a protracted time interval, with complex and evolving paleogeographic configurations much like the modern western Pacific province. Article in Journal/Newspaper Ocean Island Yukon Canadian Science Publishing Canadian Journal of Earth Sciences 41 10 1201 1235 |
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English |
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General Earth and Planetary Sciences |
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General Earth and Planetary Sciences Nelson, JoAnne Friedman, Richard Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence |
topic_facet |
General Earth and Planetary Sciences |
description |
Allochthons in the Cassiar Mountains of northern British Columbia contain assemblages belonging to two distinct Canadian Cordilleran terranes, YukonTanana (YTT) and Quesnellia. These assemblages, of pre-Late Devonian, DevonianMississippian, PennsylvanianPermian, and Early Jurassic age, occur in intrusive and depositional, as well as structural, contact with each other. The allochthons are gently dipping thrust panels, interrupted by the mid-Cretaceous Cassiar Batholith. A key element for correlation across the batholith is the Mississippian and older pericratonic Dorsey Complex. New DevonianMississippian UPb ages for deformed plutons within it document an igneous suite like those in type YukonTanana exposures farther north. Other characteristics of the Dorsey Complex that ally it with YTT are orthoquartzites and grits, and amphibolite bodies with transitional mid-ocean ridge basalt (MORB) to ocean-island basalt (OIB) petrochemical signatures. Unconformities, deformed clasts in the late Paleozoic sequences, and a shared mid-Permian intrusive suite show that later arcs onlapped the mid-Paleozoic and older YTT assemblage. The Early Jurassic intrusive suite cuts all major contacts and fabrics except the terrane-bounding fault between the Slide Mountain and combined YTTQuesnel terranes. It represents a northern continuation of a plutonic belt that extends the length of the Mesozoic Quesnel magmatic arc. These relationships carry important implications for Cordilleran terrane history and the tectonic evolution of the North American margin. At least some of the major terranes were not unrelated entities prior to their accretion to the continent, but a system of superimposed and interconnected arcs that developed over a protracted time interval, with complex and evolving paleogeographic configurations much like the modern western Pacific province. |
format |
Article in Journal/Newspaper |
author |
Nelson, JoAnne Friedman, Richard |
author_facet |
Nelson, JoAnne Friedman, Richard |
author_sort |
Nelson, JoAnne |
title |
Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence |
title_short |
Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence |
title_full |
Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence |
title_fullStr |
Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence |
title_full_unstemmed |
Superimposed Quesnel (late PaleozoicJurassic) and YukonTanana (DevonianMississippian) arc assemblages, Cassiar Mountains, northern British Columbia: field, UPb, and igneous petrochemical evidence |
title_sort |
superimposed quesnel (late paleozoicjurassic) and yukontanana (devonianmississippian) arc assemblages, cassiar mountains, northern british columbia: field, upb, and igneous petrochemical evidence |
publisher |
Canadian Science Publishing |
publishDate |
2004 |
url |
http://dx.doi.org/10.1139/e04-028 http://www.nrcresearchpress.com/doi/pdf/10.1139/e04-028 |
genre |
Ocean Island Yukon |
genre_facet |
Ocean Island Yukon |
op_source |
Canadian Journal of Earth Sciences volume 41, issue 10, page 1201-1235 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e04-028 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
41 |
container_issue |
10 |
container_start_page |
1201 |
op_container_end_page |
1235 |
_version_ |
1797571876847878144 |