GEOSCAN, résultats de la recherche


TitreTRAILS - ITH: collaborative geoscience to support infrastructure management in a changing North
AuteurMorse, P D; Kokelj, S V
Source2017 Yellowknife Geoscience Forum, abstract and summary volume; Northwest Territories Geological Survey, Yellowknife Geoscience Forum Abstract and Summary Volume 2017, 2017 p. 53-54 (Accès ouvert)
LiensOnline - En ligne (complete volume - volume complet, 1.69 MB)
Séries alt.Ressources naturelles Canada, Contribution externe 20180069
ÉditeurCommission géologique des Territoires du Nord-Ouest
Réunion45th Annual Yellowknife Geoscience Forum; Yellowknife, NT; CA; Novembre 14-16, 2017
Documentpublication en série
Mediapapier; en ligne; numérique
ProvinceTerritoires du Nord-Ouest
SNRC107B/07; 107B/10; 107B/15; 107B/16; 107C/01; 107C/02; 107C/07; 107C/08
Lat/Long OENS-134.0000 -132.5000 69.5000 68.2500
Sujetsclimat; pergélisol; glace fossile; milieu hydrologique; réseaux hydrographiques; écologie; moyens de transport; regimes thermiques; températures au sol; sediments; trous de mine; changement climatique; infrastructure; gestion; prise de décision; géologie de l'environnement; géologie de l'ingénieur; géologie des dépôts meubles/géomorphologie; géophysique; Nature et environnement; Phanérozoïque; Cénozoïque; Quaternaire
ProgrammePergélisols, Géosciences de changements climatiques
Résumé(disponible en anglais seulement)
Permafrost evolution of the western Canadian Arctic landscape is subject to unprecedented transformative pressures. Climate-driven thaw is accelerating geomorphic changes, altering hydrological systems, and affecting nutrient and carbon cycles, all of which have ecological and societal implications. As well, the new Inuvik to Tuktoyaktuk Highway (ITH) represents the largest manipulation of surface conditions in the region. In this heterogeneous, ice-rich permafrost environment, the nature of responses to these pressures, will vary with geotechnical and thermal properties of subsurface materials and landscape factors.
The Transportation Resilience in the Arctic Informed by Landscape Systems (TRAILS) activity, funded by the Climate Change Geoscience Program, NRCan, operates in partnership with Northwest Territories Geological Survey to conduct innovative permafrost research with territorial and academic partners to address questions regarding landscape change and inform infrastructure management decisions. TRAILS - ITH treats the ITH as a landscape transect for conducting multidisciplinary research on permafrost thermal conditions, terrain sensitivity, and climate change impacts on terrain and infrastructure. The research is predicated on the development of high-quality surficial geology and terrain maps, assessment of subsurface ground ice and material properties, monitoring and summary of ground thermal data, and data availability.
The first goal of this project is to work with partners to consolidate available ground temperature and geotechnical data. Secondly, we aim to improve permafrost terrain and surficial geology maps. Third, we will support the analysis and synthesis of ground ice data. The project will also analyse ground thermal data from across the treeline transition, examine local scale variability with respect to natural gradients and infrastructure, and support permafrost modelling to examine future scenarios. Finally, the project will synthesize these datasets to re-examine the role of glacial legacy and post-glacial landscape modifications on contemporary terrain sensitivity and embankment performance. Two early research activities relate to borehole and terrain mapping projects.
In February 2017, 16 thermally-instrumented boreholes were established. Multiple proxies collected are aimed at examining the suite of subsurface ground ice, geotechnical, carbon and geochemical conditions encountered across a range of environments representing ice-marginal moraine, lacustrine plain and riparian areas. This investigation revealed massive ice juxtaposed against ice-poor granular deposits; organic deposits, up to 4-5 m thick in tundra, overtop of ice-rich lacustrine deposits; and ice-poor gravels laid down on relatively near-surface silty shale. Together these data illustrate the heterogeneity implicit in this glaciated and post glacially modified landscape. Quaternary deposits and Holocene environmental history exert strong control over landscape variation and the physical, geochemical, and carbon characteristics of permafrost. Geochemical and carbon flux changes can be anticipated under warming climate conditions or as a result of physical disturbance such as quarry activities.
In May 2017, a terrain mapping exercise was initiated using very high-resolution imagery and LiDAR data to identify surficial geomorphological features and landscape types within 5 km of the ITH. These data will provide an important platform for understanding ground ice distribution and testing/validating remote sensing tools, and will facilitate assessment of landscape change and revision of the local surficial geology.
Résumé(Résumé en langage clair et simple, non publié)
Le but de l'activité de collaboration de la CGC « Résilience du transport dans l'Arctique informé par les systèmes du paysage » (TRAILS) est de mener des recherche d'avant-garde dans le domaine du pergélisol avec des partenaires territoriaux et universitaires afin de répondre à des questions concernant les changements du paysage du pergélisol et d'éclairer les décisions de gestion de l'infrastructure. TRAILS -ITH met l'accent sur la route entre Inuvik et Tuktoyaktuk, la traitant comme un transect de paysage pour effectuer des travaux de recherche multidisciplinaires sur les conditions thermiques du pergélisol, la sensibilité du terrain et les impacts du changement climatique sur le terrain et les infrastructures. La recherche est fondée sur le développement de cartes de terrain et de sédiments de surface de haute qualité, sur l'évaluation la présence de glace de sol et des propriétés des matériaux, de la surveillance et de la synthèse des données thermiques du sol, et sur la disponibilité de données. À cette étape, deux activités de recherche découlant d'analyse de trous de forage et de cartographie de terrain sont abordées.