Stability of permafrost slopes in a warming climate

Régions: Inuvialuit Settlement Region

étiquettes: physical sciences, geology, climate change, permafrost degradation, slope failure, surficial stability

chercheur principal: Dyke, Larry (10)
Nᵒ de permis: 13045
Organisation: Geological Survey of Canada
Année(s) de permis: 1999
Délivré: juil. 02, 1999
Équipe de projet: A summer student

Objectif(s): This research is a field-based approach to improving the ability to predict frozen slope instability and to anticipate the impacts of climate change. Researchers will examine the numerous slope failures along the Mackenzie Valley to determine when they occurred, calculate the material strengths of the slide zones and will calculate the amount of time that the slopes remain unstable. Landslide chronology will be established to determine what effect yearly and long term climate variability has on slope failures. Special attention will be given to forest fires as a trigger for landslides in active layer permafrost soils and the impact these slides have on landscape evolution. To further predict the impact of climate change, destabilization after landslides will also be examined to assess the effect they have on sedimentation rates in watercourses.

Description du projet: The goal of this research is to examine landslides on the slopes along the Mackenzie Valley, so that researchers can better understand their causes and the effect climate change will have on the landscape. Field work will be carried out between Wrigley and Inuvik along the Mackenzie River, with some access along the Dempster Highway. Tree increment cores will be used to determine tree age and dates of disturbance by landslides. General surveying equipment will be used to measure failure surfaces and slope angles. Excavations to the frost table will be used to examine moisture condition s at the base of the active layer. Temporary shallow cables will be installed in the active layer using 1 inch pipe water jets to a maximum depth of 10 meters. Sediment cores will be taken from lake bottoms however these are imply dropped into the mud, they do not use engines or any drilling fluids.