| Titre | Cenozoic exhumation history of the eastern margin of the northern Canadian Cordillera |
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| Auteur | McKay, R; Enkelmann, E; Hadlari, T ; Matthews, W; Mouthereau, F |
| Source | Tectonics vol. 40, issue 4, e2020TC006582, 2021 p. 1-18, https://doi.org/10.1029/2020TC006582  Accès ouvert |
| Image |  |
| Année | 2021 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20210041 |
| Éditeur | Wiley |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1029/2020TC006582 |
| Media | papier; en ligne; numérique |
| Formats | pdf; html |
| Province | Yukon; Colombie-Britannique; Territoires du Nord-Ouest |
| SNRC | 106M/09; 106M/10; 106M/11; 106M/12; 106M/13; 106M/14; 106M/15; 106M/16; 107B/03; 107B/04; 107B/05; 107B/06; 107B/11; 107B/12; 116P/09; 116P/10; 116P/11; 116P/12; 116P/13; 116P/14; 116P/15; 116P/16; 117A/01;
117A/02; 117A/07; 117A/08; 117A/09; 117A/10 |
| Région | Richardson Mountains |
| Lat/Long OENS | -138.0000 -134.0000 68.7500 67.5000 |
| Sujets | Néogène; Paléogène; antécédents tectoniques; déformation; antecedents thermiques; historique de l'enfouissement; géologie du substratum rocheux; lithologie; roches sédimentaires; roches clastiques;
datations par traces de fission; datations au zircon; apatite; établissement de modèles; tendances structurelles; Cordillère canadienne; tectonique; géochronologie; Sciences et technologie; Nature et environnement; Phanérozoïque; Cénozoïque |
| Illustrations | cartes de localisation; échelles stratigraphiques; graphiques; diagrammes; diagrammes |
| Programme | GEM2 : La géocartographie de l'énergie et des minéraux L'ouest de l'Arctique-Beaufort-nord du Yukon |
| Diffusé | 2021 02 18 |
| Résumé | (disponible en anglais seulement)
New low-temperature thermochronology data from clastic sedimentary rocks in the northern Richardson Mountains, Canada, indicate significant exhumational cooling
during late Eocene-early Oligocene time. Apatite (U-Th-Sm)/He (AHe) data were collected from 19 Proterozoic-Paleocene rocks across a 115 km transect. Eighty-eight single-grain AHe dates range from 16-300 Ma and are generally younger than
stratigraphic ages, indicative of thermal resetting by burial. Additionally, zircon (U-Th)/He (ZHe) datesfrom two Proterozoic-Cambrian rocks range from 49-123 Ma and suggest burial to >160°C. In contrast, ZHe dates from Jurassic sandstones are older
than the stratigraphic age, which limits maximum burial to <160°C.Thermal history modeling reveals three phases of cooling, during the Paleocene-early Eocene (>65-50 Ma), late Eocene-early Oligocene (40-30 Ma), and late Oligocene-early Miocene (30-15
Ma). Most samples were sensitive to cooling during the first and second phases, whereas the third phase is less well constrained. In general, most rocks were below the sensitivity of AHe analysis since the early-middle Miocene. The results suggest a
previously unrecognized phase of inferred deformation in the northern Richardson Mountains between 40-30 Ma. Our findings contribute to previous work that recognizes Late Cenozoic deformation along the eastern margin of the Northern Cordillera. We
further investigated the potential mechanisms of this widespread deformation and suggest exhumation may relate to kinematic changes of the North American plate relative to structural trends along the margin of the Northern Cordillera. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Des échantillons de roche des monts Richardson ont été analysés pour les isotopes U-Th-He afin de développer un modèle de refroidissement. Le
modèle de refroidissement se reconstitue lorsque les montagnes Richardson ont été soulevées du dessous du niveau de la mer pour former les montagnes actuelles, qui se sont produites principalement au Tertiaire environ 40 à 30 millions d'années avant
le présent. |
| GEOSCAN ID | 328299 |
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