关键词: 新构造运动, 河流地貌, 岷江, 青藏高原东缘

Abstract:

In order to further understand the Late Cenozoic tectonic activities of the Minjiang River fault, this paper studies the rivervalley landform, Cenozoic basins and planation surface in the source area of the Minjiang River so as to explain its neotectonic movement features The results show that the valley landform is characterized by the alternating wide and  narrow valleyes The source area developed three planation surfaces, which reflect strong neotectonic movement and significant landform differences Since the Neogene,the regional evolution has mainly experienced the faulted depression in the early stage(53 Ma),the thrust system accompanied by sinistral strikeslip movement in the middle stage (18 Ma), and the axially tilting uplift in the late stage(013 Ma)The landform was obviously influenced by the neotectonic movement, which formed the Quaternary fault basin, planation surface and river terraces. Neotectonic movement in this region is characterized by the SN zonation and the EW asymmetric tilting movement. This research provides morphological evidences for further study on tectonic activities in the eastern margin of the Tibetan Plateau

Key words: neotectonic movement, river-valley landform, Minjiang River, eastern margin of the Tibetan Plateau