雅鲁藏布江大峡谷则隆弄高位冰岩崩灾害链动力学特征
DYNAMIC CHARACTERISTICS OF THE ROCK-ICE AVALANCHE DISAS-TER CHAIN IN THE ZELONGNONG BASIN,YARLUNG ZANGBO RIVER CANYON REGION
高少华 1殷跃平 2李滨 3高杨 3万佳威 3张田田 3高浩源3
作者信息
- 1. 中国地质科学院地质力学研究所,北京 100081,中国;中国地质环境监测院,北京 100081,中国;自然资源部活动构造与地质安全重点实验室,北京 100081,中国
- 2. 中国地质环境监测院,北京 100081,中国;自然资源部活动构造与地质安全重点实验室,北京 100081,中国
- 3. 中国地质科学院地质力学研究所,北京 100081,中国;自然资源部活动构造与地质安全重点实验室,北京 100081,中国
- 折叠
摘要
雅鲁藏布江下游冰川分布广泛,曾发生多次高位冰岩崩事件,引发灾害链,如泥石流或碎屑流,危害巨大.本文通过野外现场调查,结合多时相卫星图像及无人机数据,以则隆弄沟为例,分析了高位灾害的地貌特征及运动动力学效应.研究表明:(1)则隆弄沟高位灾害垂向落差大,不同海拔区段微地貌形态各有差异,具有典型的垂直分带性,根据地貌展布特征及形态可划分为高陡冰蚀地形、弯曲型沟谷地形、堆积河谷地形,独特的地貌条件和地质环境使高位灾害与中低海拔地区有显著区别.(2)高位冰岩崩灾害链经历冰岩崩、碎屑流运动、堆积堵江、洪水溃决4个阶段,形成高位远程地质灾害链,运动过程中表现出复杂的动力学效应,包括冲击解体效应、散体成拱效应、动力侵蚀效应、碎屑堆积效应,为研究碎颗粒流动行为及动力学过程提供信息.(3)则隆弄冰舌处冰碛物富集,冰舌前缘及后缘分布有大量裂缝,随时间推移内部裂纹扩展累积,应力拱承载力下降而破坏致灾.未来在气候变化及强烈的构造活动影响下,雅鲁藏布江下游高位冰岩崩灾害风险极高,引发次生堵江-洪水灾害危害极大,应加强这类流域性灾害的预警及风险防范.
Abstract
The glaciers downstream of the Yarlung Zangbo River are widely distributed,with frequent occurrences of rock-ice avalanches.These avalanches often lead to secondary disasters,such as debris flows or avalanches,cau-sing significant damage.Through field investigations,combined with multi-phase remote sensing images and aerial photography,this study analyzes the geomorphic characteristics and dynamic effects of high-altitude disasters in the Zelongnong Basin.The research results reveal the following:Due to the significant vertical drop,the Zelongnong Basin exhibits typical vertical zonality.The distribution characteristics and morphology can be categorized into three geomorphic types:high and steep glacial micro-geomorphology,curved gully micro-geomorphology,and deposit mi-cro-geomorphology.The progression of the rock-ice avalanche disaster chain can be divided into four stages:rock-ice avalanches,debris flows,river blocking,and flooding.Debris flows exhibit complex dynamic effects,primarily including impact disintegration,soil-rock mixture arching,dynamic erosion,and debris deposition.These aspects provide valuable information for studying the flow behavior and dynamic processes of particles.Moraine accumula-tion is concentrated at the ice tongue,with numerous cracks distributed at the front and rear edges of the ice tongue.Over time,internal cracks expand and accumulate,leading to a decrease in stress arch bearing capacity and subse-quent damage.In the future,under the influence of climate change and strong tectonic activity,the risk of rock-ice avalanches in the downstream Yarlung Zangbo River is extremely high.Early warning systems and risk mitigation measures for basin disasters should be prioritized.
关键词
高位冰岩崩灾害链/地貌/垂直分带性/动力学效应/雅鲁藏布江Key words
Rock-ice avalanche disaster chain/Geomorphology/Vertical zonality/Dynamic effects/The Yarlung Zangbo River引用本文复制引用
基金项目
国家自然科学基金项目(U2244227)
国家自然科学基金项目(U2244226)
国家重点研发计划(2022YFC3004301)
中国地质调查项目(DD20230538)
出版年
2024
国家科技期刊平台
NSTL
万方数据