川藏铁路交通廊道地质调查工程主要进展与成果

川藏铁路是我国正在规划建设的重点工程,由于其位于地形地貌和地质构造都极为复杂的青藏高原东部,在铁路规划建设中面临一系列迫切需要解决的关键地质问题: 区域性活动断裂与断错影响、地质灾害、高地应力及其引起的岩爆和大变形、高温热害、断裂带高压水与涌水突泥、高陡边坡稳定性等。为满足技术支撑川藏铁路规划建设、精准服务国家重大战略实施的需要,中国地质调查局部署了“川藏铁路交通廊道地质调查工程”,聚焦制约川藏铁路规划建设的关键问题,充分发挥地质调查工作对国家重大工程规划建设的支撑作用。2019年主要完成铁路沿线1:5万区域地质调查1 350 km²、1:5万地质灾害调查5 000 km²,建设6口大地热流地质参数井、8个地温监测站,完成地应力测量20孔,编制完成11份地质调查专报,提出的大渡河大桥段、理塘车站段、毛垭坝盆地段等线路优化建议/防灾建议被采纳; 首次将1:5 000大比例尺航空物探技术引入复杂山地铁路工程勘察,创新形成千米级超长水平钻孔定向取心钻进技术,实现500 m深的水平孔地应力测量突破等。该工程通过2019年调查研究,全力提升了铁路沿线地质调查程度与精度,并创新了复杂艰险山区重大工程地质问题与探测技术、地质灾害风险防控理论与减灾关键技术,有效支撑服务了川藏铁路规划建设。

Main progress and achievements of the geological survey project of Sichuan-Tibet Railway traffic corridor

Sichuan-Tibet Railway is a key project planned and constructed in China. It is located in Eastern Qinghai-Tibet Plateau where the terrain, geomorphology and tectonic activity are extremely complex. There are a series of serious geological problems that need to be solved urgently in its planning and construction period, such as regional active faults with their disaster effects, high geostress with resulted rockburst and large deformation, geological hazards, high temperature with heat damage, high pressure water and mud inrush in fault zone, stability of high and steep slope. In order to support the needs of technical support for the planning and construction of Sichuan-Tibet Railway and to accurately serve the implementation of major national strategies, China Geological Survey has deployed the Geological Survey Project of Sichuan-Tibet Railway Traffic Corridor,which is focused on the key issues restricting the planning and construction of Sichuan-Tibet Railway, and plays an important role in the planning and construction of major national projects. In 2019, it mainly completed 1 350 km² of 1:50 000 regional geological survey, and 5 000 km² of 1:50 000 geological hazard survey. six geothermal flow geological parameter wells and etght earth temperature monitoring stations were also constructed. Twehty geostress measurement holes and 11 special geological survey reports were completed. The route optimizat suggestions and disaster prevention suggestions proposed for Dadu River Bridge, Litang Station, and Maoyaba Basin were adopted. The 1:5 000 large-scale aerial geophysical technology was introduced into the survey of complex mountain railway engineering for the first time, and the directional core drilling technology for ultra-long horizontal boreholes at a kilometer level was innovated with a major breakthrough. Besides, the measurement of geostress in horizontal boreholes with a depth of 500 meters was achieved. Overall, the project has improved the degree and accuracy of geological surveys along the railway through the survey and research in 2019. And the theoretical methods of major engineering geological problems and detection technologies in complex and difficult mountainous areas, geological disaster risk prevention, control theory, and key disaster reduction technologies were innovated, which effectively supported the planning and construction of Sichuan-Tibet Railway.