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

灾难性质量流的场行为；

• 批准号: RGPIN-2019-05287
• 负责人: Evans, Stephen
• 金额: $ 1.82万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=715448
• 关键词: field; behavior; catastrophic; mass; flows

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.

该研究调查了灾难性质量流的全球发生、场行为和地貌影响。灾难性物质流（CMF）涉及分解的地球物质（包括冰川冰）的快速运动，是世界许多地区的严重自然灾害。它们包括岩石雪崩、冰川雪崩、碎屑雪崩、泥石流、泥石流和泥石流。CMF经常由地震和暴雨引发；在山区冰冻圈，它们也由变暖事件引发。CMF具有潜在的破坏性；它们的场行为特点是在包括非常浅的斜坡和河道在内的一系列地形上具有高速度（50米/秒）和长跳动。值得注意的是，CMF的发生以复杂的过程链为特征，在过程链中，由于体积、材料类型或行进中添加的水的变化，初始运动转变为不同类型的运动。由于这些特点，CMF在危害评估方面提出了挑战。