• 责任者：Zhang Wei (College of Urban and Environmental Sciences ; Liaoning Normal University ; Dalian 116029 ; China) ; Bi Weili
• 刊名：Quaternary Sciences
• 出版年：2013
• 卷期：33(3)
• 关键词：冰川槽谷 ; glacial trough valley ; 横断山 ; Hengduan Mountains
• 页码：p.479-489
• 图表：illus., 5 tables, 49 refs.
• 分类号：1400
• issnNo：ISSN1001-7410
• isbnNo：CN11-2708/P

Normal style="MARGIN: 0cm 0cm 0pt">Baimaxue Shan,watershed of the Jinsha River and the Lancang River with latitude of 27°24＇ -28°36＇N and longitude of 98°57＇ -99°25＇E, is located in the inner part of the Hengduan Mountain Range and is situated between the Deqin County and Weixi County of in the northwest of the Diqing Tibetan Autonomous Prefecture,northwest of Yunnan Province. The study of the physical geographical features here has the significant meaning about both reconstructing the environmental change of the southwest monsoon and the glacial development. The definitely preserved glacial landforms and deposits indicate here was once glaciated during the Late Quaternary,especially the glacial erosive landform such as the trough valleys. Using the methods of the shape ratio, gradient ratio of wide and depth, parameters of the parabolic curve,we analysis the geomorphologic features of the simple glacial trough valleys distribute in the northeastern side of the main peak of Zhalaqueni （5429m） and the affected factors. Adopted the shape parameters of the seven profiles of these trough valleys and contrasted with other regions with well developed trough valleys,the possible reasons influenced the glacial trough valleys such as the glacial extent, type, the local climate,time span and the base rock type etc were discussed herein. The results show that the mean value of b is 1. 779 in the trough valleys of Baimaxue Shan is lower than that in the trough valleys developed in the Luoji Shan （ 1. 835） due to the different precipitation condition. However, the value of B is different from the head water of the Urtimqi（ 1. 825） indicates that the effect factors may be the glacial type,basement rock type and the time span ets. The glacial trough valley not only affected by the glacier nature but also affected by the climate condition, glacial extent,time interval and the lithology. The parameter change of the gradient ratio of wide and depth along the trough valley can reflect the dynamic change during the course of the glacial flow. According to the shoulder location of the early stage of the last glacial cycle,we estimate that the glacial equilibrium line altitude is about 4140m, and this value is consistent with 4092m confirmed by the geomorphology methods such as the cirque floor altitude,maximum altitude of the lateral moraine and the ratio of the toe to headwall. So the ancient snowline can also be determined by the altitude of the shoulder of the glacial trough valley. The parameters of the b-FR in Baimaxue Shan show that the characteristic of the glacial trough valley is not consistent with the mountainous pattern put forward by the Hiran and Aniya even in the region of maritime glacier. However, the feature of the b-FR can reflect the procedure of the glacial erosion well. The glacial erosion is mainly the lateral erosion, so the steepness of the glacial trough valley is small and the bottom of the trough valley is relative fiat and wide and shows the perfect U shape. Meanwhile, the shape ratio （b-FR） can also verify the ancient snow line altitude.