根据最新的遥感影像解译和地表调查成果,分析总结了拟建的云南大理至瑞丽铁路沿线区域最新的地表变形特征、主要活动断裂带的几何分布与运动学特征.结果显示,影响该区地壳稳定性的活动断裂带主要有10条,从东到西包括:点苍山东麓断裂、云龙-永平断裂带、保山断裂带、蒲缥-施甸断裂、太平-罗明坝断裂、镇安断裂带、龙新共轭断裂系、黄连河共轭断裂系、龙川江断裂和畹町断裂带,其中晚第四纪期间活动性最显著、对工程场地稳定性影响最大的是:点苍山东麓断裂带、保山盆地西缘断裂带、蒲缥-施甸断裂、畹町断裂带等.同时,通过整理分析近代强震资料发现,仅根据历史强震资料所揭示的高地震烈度区是不全面的,结合最新的活动断裂调查成果,对大瑞铁路沿线区域的地震烈度分区进行重新划分后,认为大瑞铁路工程场地区从东到西至少存在:大理-弥渡、保山、蒲缥-施甸、镇安-荆竹坪和瑞丽-畹町5个大于等于Ⅸ级的高地震烈度区,需要在铁路工程建设的抗震设防时给予重点关注.%The new results obtained in active fault survey show that active structure mainly consists of the Zhongdian-Dali-Ruili arcuate fault zone and active western Yunnan block around the Dali-Ruili railway in western Yunnan Province. In the active deformation area, there are ten active faults which prominently influence the crustal stability and earthquake hazard around the area along the Dali-Ruili railway. These active faults are the east piedmont fault of the Diancang Mountain, the Yunlong-Yongping fault zone, the Baoshan fault zone, the Pupiao-Shidian fault, the Taiping-Luomingba fault, the Zhen'an fault zone, the Longxin conjugated fault system, the Huanglianhe conjugated fault system, the Longchuan River fault and the Wanding fault zone from northeast to southwest. Geological and geomorphic evidence for active faulting shows that the activity of the east piedmont fault of the Diancang Mountain, the Baoshan fault zone, the Pupiao-Shidian fault, and the Wanding fault zone were evidently more stronger than other active faults during late Quaternary. Based on the historic and instrumental earthquake data and study results of active faults, the authors drew anew seismic intensity map for the area of the Dali-Ruili railway. The new earthquake intensity map shows that there are at least five high seismic intensity (intensity ^ K) areas along the Dali-Ruili railway. These areas include Dali-Midu, Baoshan, Pupiao-Shidian, Zhen'an-Jingzhuping and Wanding-Ruili from northeast to southwest
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