青藏高原巴塘断裂带地震滑坡危险性预测研究

Predicting seismic landslide hazard in the Batang fault zone of the Qinghai-Tibet Plateau

全新世以来青藏高原东部巴塘断裂带活动强烈,地形地貌和地质构造复杂,历史地震频发,并诱发大量滑坡灾害。基于巴塘断裂带地震滑坡长期防控的需要,在分析区域地质灾害成灾背景和发育分布特征的基础上,采用Newmark模型完成了巴塘断裂带50年超越概率10%的潜在地震滑坡危险性预测评价,并完成地震滑坡危险性区划。结果表明:巴塘断裂带及其临近的金沙江断裂带区域、金沙江及其支流沿岸具有较高的潜在地震滑坡危险性,地震滑坡危险区具有沿断裂带和大江大河等峡谷区分布的总体趋势,受活动断裂和地形地貌影响显著;距离断层越近、坡度越大的斜坡,地震滑坡危险性越高;规划建设中的川藏铁路经巴塘县德达乡、白玉县沙马乡,向西北延伸,跨越金沙江,可以穿越较少的地震滑坡危险区,金沙江水电工程规划建设需加强潜在地震滑坡危害研判及防控。巴塘断裂带潜在地震滑坡危险性评价结果可为区域城镇开发和重大工程规划建设的地震滑坡长期防控提供科学参考。

The Batang fault on the eastern Qinghai-Tibet Plateau has strong activity since the Holocene,where the geomorphology and geological structure is complex,and the historical earthquakes occurred frequently,which induced abundant landslides.For the long-term prevention of regional earthquake landslides in the Batang fault zone,based on analyzing the geological background and development characteristics of regional landslides,the Newmark model was used to complete the seismic landslide hazard assessment with exceeding probability 10%of 50 years in the Batang fault zone.The results show that the Batang fault zone and its adjacent Jinshajiang fault zone,the Jinsha River and its tributaries coast have the high seismic landslide hazard.The potential seismic landslide hazard zone has a general distribution trend of along the fault zone and the river canyons,which is significantly affected by the active faults and topography.The closer the slope to the fault is and the greater the slope angle is,the higher the seismic landslide hazard is.The Sichuan-Tibet Railway line under planning and construction extends from the Deda Town and Shama Town to the northwest and crosses the Jinsha River,and can traverse fewer zones with potential seismic landslide hazard.The planning and construction of Jinsha River hydropower project needs to strengthen the assessment and prevention of potential seismic landslide hazard.The potential seismic landslide hazard assessment results in the Batang fault zone can provide a scientific reference for the long-term prevention and control of earthquake landslides in the regional urban development and major engineering planning and construction.