大渡河干流流域滑坡发育时空特征与影响因素研究

Spatiotemporal development patterns and disaster-inducing factors of landslides in the main stream of Dadu River

摘要

【目的】大渡河流域位于我国青藏高原与四川盆地之间的过渡区域,区内高山耸立,河谷深切,地表起伏巨大,复杂地质条件下极易发育一系列地质灾害问题。【方法】以大渡河流域为研究区,基于多源数据融合分析方法,整合地质调查、遥感解译、时空统计分析及典型案例反演,系统构建了大渡河流域滑坡的空间分布、时间分布特征及其与地形、地质构造、岩土体类型、斜坡结构、水文条件和人类活动等多要素协同作用分析框架,研究大渡河干流流域滑坡时空演化规律并解释其多尺度耦合致灾机制。构建了多因素综合控制的滑坡发育模型,明确了研究区域地质构造与人类活动的协同作用机制。【结果】主要获得以下认识:(1)97%的滑坡发育于距断层5 km范围内,并且集中分布于海拔500~3 500 m、坡度10°~50°的强卸荷带;(2)94.18%的滑坡事件发生在5—9月雨季,与降雨量呈显著正相关;(3)水电枢纽区5 km范围内滑坡密度达0.113处/km²,是其他区域的3倍。【结论】结果表明:滑坡空间分布上呈现显著构造控灾特征,时序特征揭示降雨是滑坡发生的主要触发因素,且工程扰动诱发滑坡效应突出。

Abstract

[Objective] The Dadu River Basin, a transition between the Qinghai-Xizang Plateau and Sichuan Basin, features towering mountains, deep valleys, and dramatic relief. Complex geology renders it highly prone to geological hazards. [Methods] Via multi-source data fusion, this work integrates geological surveys, remote sensing, spatiotemporal statistics, and case inversion to establish a framework. It explores landslide spatial-temporal distribution and synergies with topography,geology, rock-soil, slope structure, hydrology, and human activities, clarifying evolution patterns and multi-scale coupled disaster mechanisms in the main basin. A multi-factor landslide model is built, and geological-human activity synergies identified. [Results] Key findings:(1) 97% of landslides occur within 5 km of faults, concentrated in strong unloading zones(500~ 3 500 m elevation, 10° ~ 50° slope);(2) 94. 18% of landslides happen in May-September rainy season, correlating significantly with rainfall;(3) Landslide density within 5 km of hydropower hubs hits 0. 113/km², triple that of other areas. [Conclusion] Result show landslide spatial distribution is strongly structure-controlled; rainfall is the main trigger, with prominent engineering disturbance effects.

关键词

工程地质 / 滑坡 / 时空特征 / 影响因素 / 大渡河流域 / 时空分布 / 遥感解译 / 地质构造

Key words

engineering geology / landslide / spatiotemporal characteristics / influencing factors / Dadu River Basin / spatiotemporal distribution / remote sensing interpretation / geological structure

基金资助

大渡河公司复杂水动力条件下滑坡监测数据可靠性评估及演变机理研究项目(KB-KY-2023-003)

四川大学山区河流保护与治理全国重点实验室开放课题资助项目(SKHL2422)

地质灾害防治与地质环境保护全国重点实验室开放基金资助项目(SKLGP2024K030)

湖北巴东地质灾害国家野外科学观测研究站开放基金项目支持(BNORSG-202406)

国家自然科学基金项目(42407230)