| Titre | Seismic anisotropy of the Canadian High Arctic: evidence from shear-wave splitting |
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| Auteur | Dubé, J -M; Darbyshire, F A; Liddell, M V; Stephenson, R; Oakey, G |
| Source | Tectonophysics vol. 789, 228524, 2020 p. 1-13, https://doi.org/10.1016/j.tecto.2020.228524  Accès ouvert |
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| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20200126 |
| Éditeur | Elsevier B.V. |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1016/j.tecto.2020.228524 |
| Media | papier; en ligne; numérique |
| Formats | pdf; html |
| Province | Nunavut |
| SNRC | 29; 38; 39; 48; 49; 58; 59; 68; 69; 78; 79; 88; 89; 98; 99; 120; 340; 560 |
| Région | Îles de la Reine-Élisabeth; île de Baffin |
| Lat/Long OENS | -124.0000 -60.0000 84.0000 72.0000 |
| Sujets | méthodes sismiques; ondes sismiques; ondes transversales; anisotropie; antécédents tectoniques; déformation; caractéristiques structurales; réseau sismique; tendances structurelles; manteau terrestre;
convection; études de la croûte; structure de la croûte; Archipel Arctique Canadien; tectonique; géologie structurale; géophysique; Sciences et technologie; Nature et environnement |
| Illustrations | cartes géolscientiques généralisées; tableaux; sismogrammes; graphiques; diagrammes stéréographiques tournant de wulff; graphiques en étoile |
| Diffusé | 2020 06 17 |
| Résumé | (disponible en anglais seulement)
The Canadian High Arctic preserves a long and complex tectonic history, including craton formation, multiple periods of orogenesis, extension and basin
formation, and the development of a passive continental margin. We investigate the possible preservation of deformational structures throughout the High Arctic subcontinental lithosphere using measurements of seismic anisotropy from shear wave
splitting at 11 seismograph stations across the region, including a N-S transect along Ellesmere Island. The majority of measurements indicate a fast-polarisation orientation that parallels tectonic trends and boundaries, suggesting that lithospheric
deformation is the dominant source of seismic anisotropy in the High Arctic; however, a sub-lithospheric contribution cannot be ruled out. Beneath Resolute in the central Canadian Arctic, distinct back-azimuthal variations in splitting parameters can
be explained by two anisotropic layers. The upper layer is oriented E-W and correlates with tectonic trends and the inferred lithospheric deformation history of the region. The lower layer has a ~NNE-SSW orientation and may arise from present-day
convective mantle flow beneath locally-thinned continental lithosphere. In addition to inferences of anisotropic structure beneath the Canadian High Arctic, measurements from the far north of our study region suggest the presence of an anisotropic
zone in the lowermost mantle beneath northwest Alaska. |
| GEOSCAN ID | 326532 |
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