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

这项研究调查了灾害性物质流的全球发生、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)的快速移动，是世界许多地区的重大自然灾害。它们包括岩石雪崩、冰川雪崩、碎片雪崩、泥石流、水流滑坡和泥石流。CMF经常由地震和暴雨触发；在山区冰冻圈，它们也是由变暖事件触发的。CMF具有潜在的破坏性；它们的野外行为以高速度(&gt；5m/S)和在包括很浅的斜坡和河道在内的一系列地形上的长时间跳动为特征。值得注意的是，CMF的发生是以复杂的过程链为特征的，在这些过程中，由于体积、材料类型或在其移动过程中添加水的变化，初始运动转变为不同类型的运动。由于这些特点，CMF在危险评估方面提出了挑战。*CMF是世界许多地区景观发展的重要因素，在某些环境中是减少地貌的主要因素。利用数字地形数据、航空照片和卫星图像的分析，结合野外观测，旨在1)探索CMF在各种地质环境中的场特征和行为，2)调查CMF在各种景观中的地貌影响，3)绘制CMF过程链的结构和行为图，4)建立CMF的景观特定的震级-时间频率关系，以及v)发展对CMF能量学的新见解。山脉景观(青藏高原和麦肯齐山脉)中的岩崩特征、沉积物储存景观中的水流滑坡(圣劳伦斯低地(加拿大东部)、和平河地区(不列颠哥伦比亚省)和黄土高原(甘肃省，中国))以及残留土壤中的快速物质运动(巴西里约热内卢州)将成为重点。*在NSERC以前资助的灾难性滑坡研究的基础上，这项工作涉及7名研究生(3名硕士和4名博士)，他们将接受灾难性滑坡分析、景观尺度地貌和高分辨率分析遥感方面的专业培训。每名学生都将针对研究提案中确定的工作目标，参加至少一次主要的地球科学会议，并对提交给同行评议期刊的科学论文做出关键的主要作者贡献。这些专家凭借他们的专门知识，将为解决加拿大在自然灾害评估和地球观测领域严重缺乏高素质专业人员的问题做出贡献。这些学生将接受适当的培训，以担任加拿大工程和遥感部门的高级专业职位，对于博士生，将接受加拿大大学学术职位的适当培训。********

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. ********