西藏地区冰崩灾害研究进展

随着全球气候的变暖,青藏高原地区冰川消融、退缩加剧,稳定性降低,增加了冰崩灾害的发生频率。西藏地区作为青藏高原的主体部分,其冰川的稳定影响着我国及周边国家的水源及生命财产安全。文章通过梳理国内外冰崩的研究现状,整理了西藏地区冰崩灾害的定义;从地形因素、构造运动和气候作用角度分析了冰崩形成机制;归纳分析了冰崩—冰湖溃决—泥石流链式灾害、冰崩—堵溃—泥石流链式灾害、冰崩—直接型泥石流（山洪）灾害3种类型冰崩灾害链的特征;阐述了目前冰崩灾害监测预警的手段及特点,认为多种监测方式联合是冰崩灾害监测的发展趋势,展望了冰崩灾害的研究体系,以期能为后续的研究工作提供思路。     

Quaternary Moraines vs Catastrophic Rock Avalanches in the Karakoram Himalaya, Northern Pakistan

A history and conception of glacial events for the central Karakoram Himalaya, proposed some 80 years ago by Giotto Dainelli, are largely accepted today. However, certain deposits identified as terminal moraine complexes marking glacial episodes were actually emplaced by rock avalanches. In the Skardu and Shigar intermontane basins of Baltistan, at least 15 rock avalanche events were previously mapped as moraine or till. Criteria used for distinguishing these catastrophic landslide deposits emphasize homogeneous lithology of rubble and matrix, clast shape, facies characteristics, the large scale unity of emplacement, and morphological relations to valley topography. The deposits of three events, at Katzarah, Satpura, and the north end of Shigar Valley, have been reconstructed in detail. Thick supraglacial debris does not result in similar deposits. Extensive valley fills, river terraces, large sediment fans, and lacustrine sediments formerly attributed to late-glacial conditions are reinterpreted as postglacial events involving rock avalanches that interrupted fluvial development. Existing reconstructions of glaciations are left in doubt, especially late-glacial events in the central Karakoram, as are the roles assigned to Karakoram, main Indus Valley, and western Himalayan ice.     

The relationship of extreme precipitation events to weather conditions in Nordland,Norway

We examined the distribution of extreme daily precipitation events (100?mm or more per day) in relation to weather conditions in the county of Nordland, Norway. Precipitation data included 88 weather stations and cover the period January 1964–March 2002. Over this period, extreme precipitation took two forms: frontal precipitation (associated with a warm or cold front) and warm sector precipitation (associated with the air masses between two fronts). Our analyses show that 57% of the extreme daily precipitation situations were classified as warm sector precipitation. This stands in contrast to claims that significant warm sector precipitation will very rarely, if ever, propagate as far north as Nordland. Because extreme precipitation may be linked to the risk of avalanches, earthflows and mudflows, it may be important to re-evaluate the forecasting criteria for heavy rain in north Norway.     

Damage Potential and Losses Resulting from Snow Avalanches in Settlements of the Canton of Grisons,Switzerland

In the field of natural hazards, risk is usually expressed as a function of probability of occurrence and damage potential. A key factor in the development of avalanche risk is a change in damage potential. In this paper, the development of damage potential and losses is analysed for settlements in the canton of Grisons, Switzerland for the period between 1950 and 2000. The spatial development patterns of the residential population and the insured value of buildings on a municipal level are described. These patterns are overlain by an accentuated occurrence of avalanches that caused damage to buildings. Extensive results from areas threatened by avalanches in the municipality of Davos are presented. Although the natural avalanche activity remained constant during the last decades, the total amount of damage decreased due to mitigation measures. The example of the municipality of Davos shows that mitigation measures are able to compensate an increase of tangible assets which leads to a reduced avalanche risk compared to earlier decades.     

大型矿床和成矿区(带)在混沌边缘

笔者将复杂性科学和矿床地质学相结合提出了一种新的金属成矿理论———“金属成矿动力系统的复杂性与自组织临界性”,并应用这一理论研究扬子古陆周缘四大成矿区（带）的矿床成因与成矿规律,发现“大型矿床和成矿区（带）在混沌边缘”。文章在概述“金属成矿动力系统的复杂性与自组织临界性”的理论纲要与噪声、混沌和混沌边缘基本概念的基础上,提出地质成矿系统在混沌边缘的四条判定准则：Ⅰ．自组织临界性的标志———广义地质学（地质学、地球物理学、地球化学）场（温度、流速、浓度、压力等场）的场量之时空幂律分布———及其基本属性：（１）长程时空关联与连通性及时空分形结构;（２）崩塌动力学;（３）“元胞自动机”的动力学机制;（４）自组织临界性涌现于“混沌边缘”,并具有最大的复杂性、演化性和创新性。Ⅱ．地质成矿过程向时间混沌及地质成矿系统向时空混沌的演化。Ⅲ．岩浆和热液“孤子”、“孤波”与“相干结构”以及其它弱混沌“拟序结构”。Ⅳ．超临界地质流体参与地质成矿作用。笔者进一步提出金属成矿动力系统的复杂性与自组织临界性的三大基础理论：（１）地质成矿过程的非线性动力学———应用非线性动力学理论研究矿床和矿集区形成的动力学机制;（２）“地质成矿作用?     

G317线汶川至马尔康段公路崩塌滑坡灾害危险性评估

为减少公路工程建设项目和地质灾害之间的相互影响,工程建设之前必须对工程建设用地存在的地质灾害进行评估。结合国道317线汶川至马尔康段公路改建工程的特点,对工程遭受或工程建设可能诱发加剧的滑坡和崩塌灾害发生的可能性作了分析,并提出相应的防治对策,为拟改建的公路建设提供指导性建议。     

The Major Snow Avalanche Cycle of February 1986 in the Western United States

Snow avalanches are a significant hazard in mountainous environments around the world. This paper investigates the major February 1986 avalanche cycle that occurred in the western United States, and broadly analyzes the avalanche, snowpack, and weather conditions at twenty sites. These analyses suggest that the avalanche cycle resulted from the interaction of a relatively `normal' snowpack with an exceptional storm event, which was particularly noteworthy for the amount of precipitation it produced. Composited 500-hPa anomaly maps show the event resulted from an uncommonly persistent blocking pattern that resulted in a strong zonal flow and copious moisture being funneled over the western United States. Understanding severe and widespread avalanche cycles may improve our long-term forecasting of these events, and help mitigate theresulting avalanche activity.     

Snow Avalanche Hazards and Management in Canada: Challenges and Progress

Avalanche impacts in Canada, including fatalities, are summarized for residential and public areas, as well as roads, ski areas, backcountry recreation, and resource industries. Methods for managing avalanche hazard, which include defence structures, zoning, forecasting and explosive control, are outlined. Problems with current avalanche hazard management are identified and progress at solving these problems is identified with an emphasis on residential areas, backcountry recreation and resource industries.