西秦岭北缘断裂带西端的活动性及其对西宁至成都铁路方案的影响-华南地震

文章信息/Info

Title:: The Activity of the West End of the Western Qinling Fault Zone and Its Influence on the Railway Project from Xining to Chengdu

Author(s):: ZHANG Zhiliang; (China Railway First Survey and Design Institute Group Co.,Ltd. Xian,710043,China)

Keywords:: Western Qinlingfault; Active fault; Ganjia basin; Planed Xining-Chengdu railway

Abstract:: The western Qinling fault zone,one of boundary faults of one secondary active block located on the northeastern margin of the Tibet Plateau,actives strongly and occurred several earthquakes with M≥6.5 in history.The planned railway project from Xining to Chengdu run through Ganjia basin adjacent to the western Qinling fault zone,so the decision of the activity and west end of the fault zone have close relations to the planed railway project. Based on the field investigation on the Quaternary geology,geomorphology and faults activity around the Ganjia basin,this paper analyzed and discussed the activity of the west end of the fault zone and its influence on the railway project.The results suggest that the western segment of the western Qinling fault zone is divided into two branch active faults ,and both of which show signs of weak Holocene surface activity. However, the west end of the fault zone terminates at the eastern margin of the Ganjia basin,and the planed railway lines does not traverse the fault zone directly in the area around the Ganjia basin.Therefore,for the railway project,it is less likely to encounter sudden offsets aroused by the western Qinling fault zone,and the seismic ground motion is the main effect to consider.