西藏边境地区地质灾害分布规律与危险性分析  

The distribution and risk assessment of geo-hazards in the border areas of Xizang

作　　者：高延超 龚凌枫 曹佳文 铁永波 卢佳燕 GAO Yanchao;GONG Lingfeng;CAO Jiawen;TIE Yongbo;LU Jiayan(Chengdu Center,China Geological Survey(Geosciences Innovation Center of Southwest China),Chengdu 610218,China;China Geological Survey,Beijing 100037,China)

机构地区：[1]中国地质调查局成都地质调查中心(西南地质科技创新中心),四川成都610218 [2]中国地质调查局,北京100037

出　　处：《沉积与特提斯地质》2024年第3期467-477,共11页Sedimentary Geology and Tethyan Geology

基　　金：四川省自然科学基金面上基金(23NSFSC0297);中国地质调查局地质调查项目(DD20221746);四川省自然资源科研项目(强震区泥石流高拦挡坝的漂木堵塞机制与库损效应研究)。

摘　　要：西藏边境地区地质灾害高发,对区内人民生命财产安全和经济建设造成严重威胁。本文搜集西藏21个边境县的地质灾害详细调查数据并进行统计分析,查明该区域共有3224处地质灾害点,包括崩塌768处、滑坡697处、泥石流1738处、冰湖溃决型链式灾害21处。其中,大型及以上的崩塌99处、滑坡48处、泥石流23处。综合区域地貌、气候特征,将西藏边境区域分为东段(南迦巴瓦峰—错那)、中段(错那—普兰)及西段(普兰—日土)。本文系统研究总结各段的地质灾害分布规律与危害特征,结合地质灾害孕灾背景及诱发因素,选取高程、坡度、水系密度、工程岩组、断裂密度、年均降雨量及地震动峰值加速度7个影响因子,基于层析分析法和加权信息量法对西藏边境地质灾害进行危险性评价,识别出察隅县察隅曲、墨脱县雅鲁藏布江段、错那县娘姆江流域、洛扎县洛扎曲、亚东县麻曲、定结县朋曲、定日县绒辖曲、聂拉木县波曲及吉隆县吉隆藏布等9个流域为地质灾害高危险区。在此基础上,本文提出了边境地区建设中需关注建设场地地质安全评价、高陡斜坡蠕滑堵江、冰湖溃决、地震灾害及其长期后效应等四个关键问题,为西藏边境地区的宏观地质灾害风险管控提供依据。A large number of geo-hazards pose a major threat to the economic growth of Xizang's border areas.This paper collects geo-hazards data from 21 border counties in Xizang,and statistics show that there are 3239 occurrences of geo-hazards in this area,including 768 collapses,697 landslides,and 1738 debris flows,among which there are 99 large or larger collapses,48 landslides,and 23 debris flows.There are also 21 glacial lake outburst disasters.Based on the characteristics of landforms and climate,the border area is divided into the eastern section(Nanjiabawa Peak-Cuona),the middle section(Cuona-Pulan),and the western section(Pulan-Ritu).The researchers systematically studied the distribution patterns and hazard characteristics of geological hazards in these different sections.The chromatographic analysis method and the information quantity method are used to analyze the risk of geo-hazards in combination with the disaster-causing mechanisms and inducing factors of the geo-hazards in this region.The selected factors include altitude,slope,aspect,water system,stratum,annual average precipitation,and peak ground acceleration.Nine watersheds were identified as high-risk areas for geological hazards.Finally,this paper puts forward following suggestions:focusing on the evaluation of geological safety at construction sites,the disaster chain of landslides and blocking rivers,and the long-term effects of earthquakes,in order to provide a basis for the management and control of geo-hazards risk in the border areas of Xizang.

关 键 词：西藏 边境地区 地质灾害 分布规律 危险性评价 

分 类 号：P694[天文地球—地质学]