Understanding rock slope failure and coseismic landslide hazard in deglaciated Cordilleran landscapes

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Rock slope failures are a major source of landslide hazards in Cordilleran landscapes, which are typically characterized by high altitudes, large relief and dynamic hillslope, fluvial and glacial processes. While rock falls pose a localized threat to urban areas and transport corridors, large volume rock slides can result in destructive, long runout rock avalanches, debris flows and outburst floods that affect large areas. For example, the 1970 Mt. Huascaran landslide in Peru caused thousands of deaths. More recently, the 2021 Chamoli rock avalanche in the Indian Himalayas damaged two power plants and killed over 200 people. In western Canada there are several examples of large rock slope failures, such as the 1903 Frank slide, the 1965 Hope slide and the 2010 Mt. Meager slide. Accelerated glacier retreat due to climate change is increasing the likelihood of slope failures. Furthermore, southwestern British Columbia is located in an area of high seismic hazard, but the risk of landslides induced by large earthquakes is not well understood. The overarching long-term goal of my research program is to understand the factors controlling rock slope failures at different scales in deglaciated high mountain settings, and how the spatial distribution and evolution of such factors in geological time influence the present-day hazard of large rock slides, falls and avalanches. Moreover, I aim to understand how large earthquakes may induce failure in marginally stable deglaciated rock slopes. The short-term objectives of the proposed research are to: 1) Improve understanding of geotechnical and geological controls on rock slope stability, 2) Evaluate the influence of glacier dynamics on the deformation response and stability of the slopes, and 3) Assess the hazard of earthquake-induced landslides in likely earthquake scenarios. My group will carry out extensive engineering geological field reconnaissance for selected case studies, remote sensing data acquisition and processing, and 2D and 3D geotechnical numerical modelling at different temporal and spatial scales. With the resulting models, we will investigate processes such as progressive failure, glacier-slope interaction in glacier margins and the effect of seismic shaking in rock slopes. The expected outcomes will expand scientific understanding of complex slope processes in high mountain landscapes, contribute to training of HQP in cutting-edge applied geosciences and geo-engineering skills, and form the basis for interdisciplinary research and international collaboration with researchers in engineering geology and geohazards. The research program will benefit Canada by providing new knowledge for improved landslide hazard assessment in the context of climate change and seismic risk. Our results will improve the design of engineering and land planning tools for disaster risk reduction, preventing loss of lives and critical infrastructure in the Canadian Cordillera and mountain regions worldwide.