滇藏铁路沿线重要活动断裂带晚第四纪活动性初步研究

Preliminary study on the Late Quaternary activity of important active fault zones along the Yunnan-Tibet railway

滇藏铁路位于青藏高原东南缘板块碰撞和构造活跃的地形急变带,沿线活动断裂发育,地震频发,地震烈度强,且地质灾害频繁,其规划施工建设和长期运营面临的地质安全风险问题严峻。滇藏铁路香格里拉—波密段沿线发育了哈巴—玉龙雪山东麓断裂带、中甸—龙蟠断裂带、德钦—中甸—大具断裂带、维西—乔后断裂带、金沙江断裂带、巴塘断裂带、澜沧江断裂带、怒江断裂带、边坝—洛隆断裂带、嘉黎—察隅断裂带等10余条活动断裂带。受断裂黏滑位错、蠕滑变形和引发强震风险的突出影响,迫切需要厘定区域活动断裂带的几何展布和活动性。基于前人资料、遥感解译和野外调查,本文总结分析了沿线10余条活动断裂带的几何展布、运动性质、滑动速率和古地震历史等,以期为滇藏铁路等国家重大工程规划建设与安全运营提供基础资料。

The Yunnan-Tibet railway is located in the southeastern edge of the Tibetan Plateau,where tectonic plates collide and the terrain rapidly changes.Along the line,active faults develops,earthquakes occur frequently,and the intensity of earthquakes is strong,moreover,geological disasters are frequent.Hence its planning,construction,and long-term operation face severe geological safety risks.More than 10 active fault zones have been developed along the Shangri La-Bomi section of the Yunnan-Tibet railway,including the Haba-Yulong Snow Mountain east foot fault zone,Zhongdian-Longpan fault zone,Deqin-Zhongdian-Daju fault zone,Weixi-Qiaohou fault zone,Jinsha river fault zone,Batang fault zone,Lancang river fault zone,Nujiang fault zone,Bianba-Luolong fault zone,and Jiali-Chayu fault zone.These active fault zones are highly affected by fault slip dislocations,creep deformation,and the risk of triggering strong earthquakes.There is an urgent need to determine the geometric distribution and activity of regional active fault zones.Based on previous research,remote sensing interpretation,and field investigations,this article summarizes and analyzes the geometric distribution,kinematic properties,slip rate and paleoearthquake sequence of more than 10 active fault zones along the route,providing basic information for the planning,construction and safe operation of major national projects such as the Yunnan-Tibet railway.