摘要
2010年8月18日云南省贡山县普拉底乡东月各沟暴发泥石流,造成了严重的人员伤亡和财产损失,是近年来发生于我国滇西北三江成矿带最严重的特大泥石流事件,同时也是泥石流危害矿产资源开发和利用的典型案例,分析其成因与防灾对策对未来该区域的发展规划,矿产资源的开发和利用,以及防灾减灾对策的制定具有重要的参考价值和警示意义。根据实地调查,结合遥感影像与气候资料分析,研究区的活动断层与1950年西藏察隅地震对东月各沟造成了严重影响,形成区的寒冻风化与第四纪冰川的作用加速了泥石流物源累计的速率,陡峻的地形和1200万m3的巨量冰碛物是泥石流灾害发生的根本原因;气候变化,尤其是暴雨日数的异常增加与气温的快速变化是灾害发生的诱因,当日的11.0mm/h的短历时、高强度降雨和高温天气是最终的激发因素;此外,需要注意的是,流域内选矿厂工人对泥石流灾害警惕意识不高也是造成此次灾难的重要原因。根据贡山县的实际情况,结合怒江流域泥石流分布密度较高的特点,建议贡山县在未来的矿产资源的开发和利用过程中,必须兼顾开发利用和环境保护,据此提出了针对矿产资源开发利用的泥石流防灾减灾对策。
A mega extra-large debris flow occurred in Dongyuege Gully, Puladi Township, Gongshan county, Yunan province on, Aug. 18, 2010, which caused 92 deaths or missing and with a loss amounting to RMB140 million. The debris flow destroyed an iron concentrator and temporarily blocked the mainstream of Nujiang River. This proves a typical event that causes tremendous disasters to mineral resources in the metallogenic belt of Tthree Parallel Rivers region, northwest part of Yunnan province. Study of the occurrence is believed to be helpful for the strategy decision and regional development program of hazard mitigation in utilizing mineral resources. Field surveys in combination with analysis of remote sensing images and climate data indicate that the gullies hadve been seriously impacted by the Chayu earthquake in 1950 and the regional active faults, such as Nujiang falut belts, Langcanjiang fault belts and Puladi-Caojian fault; at the same time, frost weathering and glacial erosion had accelerated the accumulation rate of solid loose materials, especially moraine. Debris flow formation are hasmainly due to three reasons: 1) The steep terrain and"V"shape channel provided beneficial convergence conditions for the formation of debris flow; 2) A huge moraine of 12 million m 3 is the primary cause provide very abundant material supplies for debris flow occurrence, which is essential cause of the disaster; 3) The dramatic increase of rainstorm and rapid changes in temperature are incentivesthe induced factors, at last precipitation with a high-intensity of 11.0mm/h as well asand short time and high temperature are the direct factors that triggering the occurrence. Besides, the insensitivity of dressing plant workers local people to debris flow increases the loss of lives although mining slags were not involved in the debris flow activity. So far, the sediment volume carried out from the Dongyuege gully is only 3.5 million m 3 , and the left materials with a volume of 8.5million are still of high risk of triggering debris flows and blocking the Nujiang River. The debris flow of Dongyuege gulley have been givesn us a warning signal: the countermeasures and forecasting system against debris flow are necessary for during utilization of mineral resources utilization along Nujiang, Lancangjiang, Jinshajiang rivers metallogenic belts. Local government and enterprises must keep a balance between development and environment protection. To do this, comprehensive engineering measures and an effective system of monitoring and forecasting for debris flow need to be established based on improvement of peoples’ consciousness of preventing hazards and the ability of saving themselves.
出处
《资源科学》
CSSCI
CSCD
北大核心
2012年第7期1248-1256,共9页
Resources Science
基金
国家科技基础性工作专项(编号:2008FY110300-06)
科技支撑计划课题(编号:2008BAK50B04)
关键词
贡山县
泥石流
矿产资源
气候变化
Gongshan county
Debris flow
Mineral resources
Utilization and development
Causale
Countermeasure against disaster
Climate change