金沙江上游色拉古滑坡复活特征与堵江溃决模拟分析  

Reactivation characteristics and river blocking outburst simulation analysis of Sela ancient landslide in the upper reaches of Jinsha River

作　　者：胡贵良 刘文 鄢勇 范雄安 张毅 杜光远 熊皓 王猛 余天彬 HU Guiliang;LIU Wen;YAN Yong;FAN Xiongan;ZHANG Yi;DU Guangyuan;XIONG Hao;WANG Meng;YU Tianbin(Huadian Jinsha River Upstream Hydropower Development Co.,Ltd.,Chengdu,Sichuan 610095,China;Sichuan Institute of Comprehensive Geological Survey(Evaluation and Utilization of Strategic Rare Metals and Rare Earth Resource Key Laboratory of Sichuan Province),Chengdu,Sichuan 610081,China;Huadian Jinsha River Upstream Hydropower Development Co.,Ltd.Batang Branch(Lawa Branch),Ganzi,Sichuan 627650,China;Huadian Jinsha River Upstream Hydropower Development Co.,Ltd.Yebatan Branch,Ganzi,Sichuan 627153,China)

机构地区：[1]华电金沙江上游水电开发有限公司,四川成都610095 [2]四川省综合地质调查研究所(稀有稀土战略资源评价与利用四川省重点实验室),四川成都610081 [3]华电金沙江上游水电开发有限公司巴塘分公司(拉哇分公司),四川甘孜627650 [4]华电金沙江上游水电开发有限公司叶巴滩分公司,四川甘孜627153

出　　处：《地质学报》2025年第2期602-615,共14页Acta Geologica Sinica

基　　金：四川省地质调查研究院财政资金项目(编号SCIGS-CZDXM-2024006);华电金沙江上游水电开发有限公司科研项目(编号JS-LW-FW/ZX-084,JS-YBT-FW/YF-2022-30);部-省合作四川地质灾害遥感项目(编号SCDZRS-2023)联合资助的成果。

摘　　要：色拉古滑坡位于金沙江结合带内,地表复活变形迹象明显,存在大规模失稳的风险,极可能形成滑坡-堵江-洪水灾害链。本文采用光学遥感影像动态监测、工程地质调查、数值模拟等方法,探讨了色拉古滑坡的复活变形特征,开展了滑坡稳定性和堵江溃决模拟分析。结果表明:色拉古滑坡为特大型滑坡,体积约6300×10^(4)~9500×10^(4) m^(3),滑体物质为碎块石土,滑床物质为二叠系—下三叠统岗托岩组云母石英片岩,目前处于蠕滑变形阶段,2018年至2023年存在持续变形,主要集中在斜坡前缘。色拉滑坡沿古滑动面复活滑动,表现为牵引式渐进破坏,在稳定性分析的基础上,建立了4种潜在失稳模式:天然工况下,Ⅲ-2区失稳,持续过程约35 s,滑体最大速度约30 m/s,堵江堰塞坝高度约97 m,堰塞湖库容约1.56×10^(8) m^(3),堰塞坝溃决后拉哇电站坝址处最大洪水流量约3650 m^(3)/s,最大洪峰高度约14 m;天然工况下,Ⅲ-3区或Ⅲ-4区单独失稳,堵江堰塞坝高度约88~90 m,堰塞湖库容约1.22×10^(8) m^(3),堰塞坝溃决后拉哇电站坝址处最大洪水流量约2900 m^(3)/s,最大洪峰高度约12 m;地震工况下,Ⅱ区、Ⅲ区同时失稳,堵江堰塞坝高度约152 m,堰塞湖库容约5.88×10^(8) m^(3),堰塞坝溃决后拉哇电站坝址处最大洪水流量约19270 m^(3)/s,最大洪峰高度约44 m。色拉滑坡堵江风险高、致灾性强,建议采用天空地一体化的手段对色拉滑坡持续监测,最大限度地减少堵江滑坡链式灾害造成的人员伤亡和财产损失。The Sela ancient landslide,located in the Jinshajiang suture belt,exhibits obvious signs of reactivation deformation,posing a significant risk of large-scale instability,potentially leading to a landslide,river blockage,and subsequent flood disaster chain.This study uses optical remote sensing dynamic monitoring,engineering geological surveys,and numerical simulation to analyze the reactivation deformation characteristics,simulate the stability,and predict the potential river-blocking outburst of the Sela ancient landslide.The results indicate that the Sela ancient landslide is a huge landslide with an estimated volume of 6300×10^(4) to 9500×10^(4) m^(3).The sliding mass comprises broken stone and soil,while the sliding bed consists of mica quartz schist belonging to the Permian to Lower Triassic Gangtuo Rock Group.The landslide displays obvious signs of reactivation deformation,currently in a stage of creep deformation.Continuous deformation has been observed from 2018 to 2023,mainly concentrated at the front edge of the slope.The Sela ancient landslide reactivates and slides along the pre-existing sliding surface,exhibiting traction-type progressive failure mechanisms.The stability analysis identified four potential instability modes.Under natural conditions,zoneⅢ-2 is unstable,with a landslide duration of about 35 seconds.The maximum landslide speed reaches 30 m/s.The resulting barrier dam would be approximately 97 m high,creating a barrier lake with a capacity of about 1.56×10^(8) m^(3).The failure of this dam would generate a maximum flood flow of approximately 3650 m^(3)/s and a maximum flood peak height of approximately 14 m at the Lava Power Station dam site.Similarly,under natural conditions,if zonesⅢ-3 zone orⅢ-4 become unstable,the barrier dam height would be around 88 to 90 m,with a barrier lake capacity of approximately 1.22×10^(8) m^(3).The dam failure would result in a maximum flood flow of approximately 2900 m^(3)/s and a maximum flood peak height of approximately 12 m at the Lava Power

关 键 词：复活特征 数值模拟 堵江溃决 金沙江上游 色拉古滑坡 

分 类 号：P64[天文地球—地质矿产勘探]