The field behavior of catastrophic mass flows; hazard assessment and geomorphic impact

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The study investigates the global occurrence, field behaviour and geomorphic impact of catastrophic mass flows. Catastrophic mass flows (CMF) involve the rapid movement of disaggregated earth materials (including glacier ice) and are critical natural hazards in many parts of the world. They include rock avalanches, glacier avalanches, debris avalanches, debris flows, flowslides, and debris floods. CMF are frequently triggered by earthquakes and heavy rains; in the mountain cryosphere they are also triggered by warming events. CMF are potentially destructive; their field behaviour is characterised by high velocity (>5m/s) and long-runout over a range of topography, including very shallow slopes and river channels. Notably, the occurrence of CMF is characterised by complex process chains in which an initial movement is transformed into a different type of movement due to changes in volume, material type, or the addition of water in its travel. Because of these characteristics CMF present challenges in hazard assessment. CMF are important agents of landscape development in many regions of the world and in some environments are the main agent of relief reduction. Utilising the analysis of digital topographic data, aerial photographs and satellite images together with field observations, it is intended to i) explore the field characteristics and behaviour of CMF in a range of geologic environments, ii) investigate the geomorphic impact of CMF in a variety of landscapes, iii) map the architecture and behaviour of CMF process chains, iv) develop landscape-specific magnitude-temporal frequency relations for CMF, and v) develop new insight into CMF energetics.. The characterisation of rock avalanches in mountain landscapes (Tibetan Plateau and Mackenzie Mountains), flowslides in sediment-storage landscapes (St. Lawrence Lowlands (Eastern Canada), Peace River region (British Columbia) and Loess Plateau (Gansu Province, China)), and rapid mass movements in residual soils (Rio de Janeiro State, Brazil) will form a special focus. Building on previous NSERC-funded research on catastrophic landslides, the work involves 7 graduate students (3 MSc and 4 PhD) who will receive specialist training in the analysis of catastrophic landslides, landscape-scale geomorphology, and high-resolution analytical remote sensing. Each student will address a working objective identified in the research proposal, participate in at least one major geoscience conference, and make key lead-author contributions to scientific papers submitted to peer-reviewed journals. With their niche-expertise, these specialists will contribute to meeting Canada's critical shortage of highly-qualified professionals in the fields of natural hazard assessment and earth observation. The students will be suitably trained for senior professional positions in the Canadian engineering and remote sensing sectors and, in the case of the PhD students, for academic positions at Canadian universities.