| Titre | High-resolution mapping of glacial landscapes in central mainland Nunavut using ArcticDEM data and Landsat 8 imagery |
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| Auteur | McMartin, I ;
Godbout, P -M; Campbell, J E; Tremblay, T; Behnia, P |
| Source | GSA 2020 Connects Online - Geological Society of America Annual Meeting; Geological Society of America, Abstracts With Programs vol. 52, no. 6, 129-3, 2020 p. 1, https://doi.org/10.1130/abs/2020AM-354703 |
| Image |  |
| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20200344 |
| Éditeur | Geological Society of America |
| Réunion | GSA 2020: Geological Society of America Annual Meeting 2020; Octobre 26-30, 2020 |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1130/abs/2020AM-354703 |
| Media | papier; en ligne; numérique |
| Formats | html; pdf |
| Province | Nunavut |
| SNRC | 46D; 46E; 46F; 46K; 46L; 46M; 46N; 55; 56; 65A; 65B; 65G; 65H; 65I; 65J; 65O; 65P; 66A; 66B; 66G; 66H; 66I; 66J; 66O; 66P |
| Région | Baie d'Hudson; Wager Bay; Baker Lake; Rankin Inlet; Arviat; Naujaat |
| Lat/Long OENS | -100.0000 -85.0000 68.0000 60.0000 |
| Sujets | antecedents glaciaires; glaciation; nappes glaciaires; déglaciation; elements glaciaires; topographie glaciaire; écoulement glaciaire; paléoenvironnement; transport des sediments; dispersion des
sédiments; prospection minière; exploration de dépôts glaciaires; climat; Calotte glaciaire Laurentide; Carte géologique; directions d'écoulement glaciaire; courants glaciaires; lignes de partage glaciaire; Données géographiques; Système
d'information géographique; Changement climatique; géologie des dépôts meubles/géomorphologie; géologie de l'environnement; géologie économique; Nature et environnement; Sciences et technologie; Phanérozoïque; Cénozoïque; Quaternaire |
| Programme | GEM2 : La géocartographie de l'énergie et des minéraux Synthèse de l'histoire glaciaire de la province de Rae |
| Diffusé | 2020 10 01 |
| Résumé | (disponible en anglais seulement)
A new glacial geomorphology map was produced for an area covering ~415,000 km2 in a core region of the Laurentide Ice Sheet (LIS) in Nunavut. The map builds on
recent and legacy surficial geology maps and is significantly improved by digitization of glacigenic features using a combination of high-resolution ArcticDEM data (2-m resampled to 5-m resolution) and Landsat 8 images (30-m pansharpen to 15-m). Data
comprised of glacial geomorphological features were individually identified (lines and points) or grouped in generalized areas (polygons). Information (metadata) was stored in attribute tables for each mapped feature, including feature type, subtype
(if distinguished), and original map data source and/or nature of modification or addition.
From this unprecedented, detailed inventory of ~152,000 features and >14,000 field observations, we identify and map coherent patterns of landform
development (landsystems) between the Manitoba border and the Arctic coast, many of which are entirely new and others that are significantly modified or updated. In particular, we recognize six separate ice streams and delineate numerous palimpsest
streamlined landscapes with associated ice flow trends and relative ages. A continuum of relict terrains with varying basal ice thermal conditions is mapped for the first time in the ice divide migration zone between Baker Lake and Wager Bay. In
addition, deglacial cold-based retreat terrains and preserved warm-based landscapes unaffected by younger glacial events have been identified.
The final products consist of: generalized glacial geomorphology maps at 1:5 million and 1:1 million
scales; an interpretation of entirely new or updated glacial landsystems; and a bibliography of all published sources of information. The GIS data files comprise glacial features mapped at original scales, standardized field datasets and glacial
landsystems overlays. These new georeferenced, multi-scale datasets provide a comprehensive framework to strengthen reconstructions of the glacial history and dynamics of one of the largest ice dome of the LIS, help identify distinct glacial sediment
transport paths for applications to mineral exploration, and test numerical modelling of the LIS in support of climate change studies and long-term evolution of modern ice sheets. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Cette affiche présente une nouvelle carte de la géomorphologie glaciaire synthétisant une base de données complète des anciens paysages
glaciaires dans une vaste zone du Nunavut continental, dans le cadre de l'activité GEM-2 Histoire et dynamique glaciaire du Projet Rae. L'affiche met en évidence les diverses sources de données, les méthodes de cartographie à l'aide d'images haute
resolution et les interprétations des grands systèmes de terrains glaciaires. Le travail a été entrepris dans le but de fournir de nouvelles connaissances géologiques sur l'histoire glaciaire du Keewatin et d'aider la compréhension du transport
glaciaire en terrain englacé dans la région. Les résultats appuieront le processus de prise de décisions pour l'exploration des ressources et l'utilisation des terres. |
| GEOSCAN ID | 327032 |
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