| Titre | Distribution and morphometry of pingos, western Canadian Arctic, Northwest Territories, Canada |
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| Auteur | Wolfe, S A ;
Morse, P D; Parker, R |
| Source | Geomorphology 108694, 2023 p. 1-12, https://doi.org/10.1016/j.geomorph.2023.108694 |
| Image |  |
| Année | 2023 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20220351 |
| Éditeur | Elsevier |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1016/j.geomorph.2023.108694 |
| Media | papier; numérique; en ligne |
| Référence reliée | Photo(s) de RNCan dans cette publication |
| Formats | pdf; html |
| Province | Territoires du Nord-Ouest |
| SNRC | 107A; 107B; 107C; 107D; 107E; 107F; 117A; 117D; 117E |
| Lat/Long OENS | -136.4294 -128.5419 70.3164 68.0331 |
| Sujets | pergélisol; pingos; Sciences et technologie; géologie générale |
| Illustrations | photographies; diagrammes; cartes de localisation |
| Programme | Géosciences de changements climatiques Pergélisols |
| Diffusé | 2023 04 08 |
| Résumé | (disponible en anglais seulement)
Pingos of the western Canadian Arctic (WCA) coastal plain are among the most abundant and well-studied in the northern hemisphere. However, the abundance and
morphometric variation of these pingos has not been quantitatively examined with respect to surficial and physiographic settings, likely because they have never been systematically catalogued with precision. We assess the distribution and morphology
of pingos in the WCA using the High Resolution Digital Elevation Model (HRDEM) and demonstrate how this population compares to others in the Arctic, and how it varies in relation to surficial and physiographic settings. Of the 2363 pingos identified
in the WCA (900 more than previous estimates), relief ranges from a few 10s of centimetres to 46.7m for Ibyuk Pingo, which is the archetype of closed-system (hydrostatic) pingos in the region. Nearly 18% (272) are taller than 10m, although about 35%
of the pingos (830) are <2m tall, which is the minimum height limit of most other studies. Using this minimum cut-off to compare populations, the mean height of WCA pingos >2m (n=1533) is 6.5m, which is greater than other lowland pingos in the
Arctic. WCA pingos are about 10% larger in radius than pingos in North Alaska but have comparable mean slopes. Nevertheless, about 72% of WCA pingos > 2m tall are "high-slope" pingos with a mean slope of 5° or greater. Within the WCA, 95% of all
pingos occur within the Tuktoyaktuk Lowlands in relation to the distribution of underlying Pleistocene sands, specifically the extent of braidplain deposits from the paleo-Peel and Anderson rivers known as the Kidluit Formation (Marine Isotope Stage
3). However, the spatial density of pingos within the Tuktoyaktuk Lowlands varies with physiography, and the highest densities relate to ice-rich, topographically-complex terrains that have a history of glaciation and thermokarst. In contrast, pingos
within the modern Mackenzie Delta, where the low-lying, Holocene-age terrain is not amenable to lake drainage that promotes closed-system pingo formation, have a low density (5% of total population) and are smaller. Nearly 30% of WCA pingos reside at
<5m asl. Consequently, ongoing relative sea level rise and the effects on coastal change are likely to erode some pingos within the current population but may also trigger lake drainage and formation of new pingos. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Nous avons cartographié et mesuré la distribution et les caractéristiques des pingos dans les terres côtières de Tuktoyaktuk, Territoires du
Nord-Ouest Canada. Il y a 2363 pingos dans la région. C'est la plus forte densité de pingos de l'hémisphère nord. La taille moyenne des pingos est plus grande et plus grande que les pingos dans d'autres régions de l'Arctique. La distribution des
pingos est liée à l'étendue des sables fluviaux sous-jacents et à la complexité du paysage. Les zones de drainage interconnecté ont une plus grande abondance de pingos que les zones de petits bassins de lacs fermés. |
| GEOSCAN ID | 330887 |
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