The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution
The Laberge Group is an Early to Middle Jurassic sequence of mostly siliciclastic sedimentary rocks that were deposited in a marginal marine environment in the northern Canadian Cordillera. It forms a long narrow belt with a total thickness of 3–4 km extending for more than 600 km across southern Yu...
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ftuninewbrunojs:oai:ojs.journals.lib.unb.ca:article/32539 2023-05-15T18:44:10+02:00 The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution Kellett, Dawn A. Zagorevski, Alex 2022-03-26 application/pdf https://journals.lib.unb.ca/index.php/GC/article/view/32539 eng eng Geological Association of Canada https://journals.lib.unb.ca/index.php/GC/article/view/32539/1882528020 https://journals.lib.unb.ca/index.php/GC/article/view/32539 Copyright (c) 2022 Geoscience Canada Geoscience Canada; Vol. 49 No. 1 (2022); 7–27 1911-4850 0315-0941 British Columbia Canadian Cordillera Detrital zircon Jurassic Laberge Group Thermochronology Whitehorse trough info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion research-article 2022 ftuninewbrunojs 2022-07-11T11:48:39Z The Laberge Group is an Early to Middle Jurassic sequence of mostly siliciclastic sedimentary rocks that were deposited in a marginal marine environment in the northern Canadian Cordillera. It forms a long narrow belt with a total thickness of 3–4 km extending for more than 600 km across southern Yukon and northwestern British Columbia. These sedimentary rocks overlap the Yukon-Tanana, Stikinia and Cache Creek terranes that form the main components of the Intermontane superterrane. The Laberge Group contains a record of the erosion of some of these terranes, and also offers some constraints on the timing of their amalgamation and accretion to the Laurentian margin. The Laberge Group was deposited with local unconformity on the Late Triassic Stuhini Group (in British Columbia) and correlative Lewes River Group (in Yukon), both of which are volcanic-rich, and assigned to the Stikinia terrane. The Laberge Group is in turn overlain by Middle Jurassic to Cretaceous clastic rocks, including the Bowser Lake Group in BC and the Tantalus Formation in Yukon. Clast compositions and detrital zircon populations within the Laberge Group and between it and these bounding units indicate major shifts in depositional environment, basin extent and detrital sources from Late Triassic to Late Jurassic. During the Early Jurassic clast compositions in the Laberge Group shifted from sediment- and volcanic-dominated to plutonic-dominated, and detrital zircon populations are dominated by grains that yield ages that approach or overlap their inferred depositional ages. This pattern is consistent with progressive dissection and unroofing of (an) active arc(s) to eventually expose Triassic to Jurassic plutonic suites. Detrital rutile and muscovite data from the Laberge Group indicate rapid cooling and then exhumation of adjoining metamorphic rocks during the Early Jurassic, allowing these to contribute detritus on a more local scale. The most likely source for such metamorphic detritus is within the Yukon-Tanana terrane, and its presence in ... Article in Journal/Newspaper Whitehorse Yukon University of New Brunswick: Centre for Digital Scholarship Journals Bowser ENVELOPE(-155.600,-155.600,-86.050,-86.050) Bowser Lake ENVELOPE(-129.563,-129.563,56.444,56.444) Yukon |
institution |
Open Polar |
collection |
University of New Brunswick: Centre for Digital Scholarship Journals |
op_collection_id |
ftuninewbrunojs |
language |
English |
topic |
British Columbia Canadian Cordillera Detrital zircon Jurassic Laberge Group Thermochronology Whitehorse trough |
spellingShingle |
British Columbia Canadian Cordillera Detrital zircon Jurassic Laberge Group Thermochronology Whitehorse trough Kellett, Dawn A. Zagorevski, Alex The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution |
topic_facet |
British Columbia Canadian Cordillera Detrital zircon Jurassic Laberge Group Thermochronology Whitehorse trough |
description |
The Laberge Group is an Early to Middle Jurassic sequence of mostly siliciclastic sedimentary rocks that were deposited in a marginal marine environment in the northern Canadian Cordillera. It forms a long narrow belt with a total thickness of 3–4 km extending for more than 600 km across southern Yukon and northwestern British Columbia. These sedimentary rocks overlap the Yukon-Tanana, Stikinia and Cache Creek terranes that form the main components of the Intermontane superterrane. The Laberge Group contains a record of the erosion of some of these terranes, and also offers some constraints on the timing of their amalgamation and accretion to the Laurentian margin. The Laberge Group was deposited with local unconformity on the Late Triassic Stuhini Group (in British Columbia) and correlative Lewes River Group (in Yukon), both of which are volcanic-rich, and assigned to the Stikinia terrane. The Laberge Group is in turn overlain by Middle Jurassic to Cretaceous clastic rocks, including the Bowser Lake Group in BC and the Tantalus Formation in Yukon. Clast compositions and detrital zircon populations within the Laberge Group and between it and these bounding units indicate major shifts in depositional environment, basin extent and detrital sources from Late Triassic to Late Jurassic. During the Early Jurassic clast compositions in the Laberge Group shifted from sediment- and volcanic-dominated to plutonic-dominated, and detrital zircon populations are dominated by grains that yield ages that approach or overlap their inferred depositional ages. This pattern is consistent with progressive dissection and unroofing of (an) active arc(s) to eventually expose Triassic to Jurassic plutonic suites. Detrital rutile and muscovite data from the Laberge Group indicate rapid cooling and then exhumation of adjoining metamorphic rocks during the Early Jurassic, allowing these to contribute detritus on a more local scale. The most likely source for such metamorphic detritus is within the Yukon-Tanana terrane, and its presence in ... |
format |
Article in Journal/Newspaper |
author |
Kellett, Dawn A. Zagorevski, Alex |
author_facet |
Kellett, Dawn A. Zagorevski, Alex |
author_sort |
Kellett, Dawn A. |
title |
The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution |
title_short |
The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution |
title_full |
The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution |
title_fullStr |
The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution |
title_full_unstemmed |
The Jurassic Laberge Group in the Whitehorse Trough of the Canadian Cordillera: Using Detrital Mineral Geochronology and Thermochronology to Investigate Tectonic Evolution |
title_sort |
jurassic laberge group in the whitehorse trough of the canadian cordillera: using detrital mineral geochronology and thermochronology to investigate tectonic evolution |
publisher |
Geological Association of Canada |
publishDate |
2022 |
url |
https://journals.lib.unb.ca/index.php/GC/article/view/32539 |
long_lat |
ENVELOPE(-155.600,-155.600,-86.050,-86.050) ENVELOPE(-129.563,-129.563,56.444,56.444) |
geographic |
Bowser Bowser Lake Yukon |
geographic_facet |
Bowser Bowser Lake Yukon |
genre |
Whitehorse Yukon |
genre_facet |
Whitehorse Yukon |
op_source |
Geoscience Canada; Vol. 49 No. 1 (2022); 7–27 1911-4850 0315-0941 |
op_relation |
https://journals.lib.unb.ca/index.php/GC/article/view/32539/1882528020 https://journals.lib.unb.ca/index.php/GC/article/view/32539 |
op_rights |
Copyright (c) 2022 Geoscience Canada |
_version_ |
1766234757560008704 |