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龙门山位于青藏高原东缘,既是青藏高原周缘山脉中陡度最大的山脉,也是构造活动和地貌景观塑造最为强烈的地区之一。因此,该区域成为研究构造-地貌-水系之间相互关系的实验场。本文基于ASTER GDEM数据,提取了青藏高原东缘地区15条基岩河道的纵剖面,采用简单数学函数拟合河流纵剖面形态,并结合基岩水力侵蚀模型,分析龙门山不同位置的地形特征。本次研究获得以下几点认识:①通过对龙门山地区河流纵剖面的分析,龙门山整体上具有较高的隆升速率,导致这一地区强烈的河流侵蚀作用;②龙门山中段和南段的河流双对数图以上凸型为主,说明该区域尚未达到均衡状态,处于前均衡期;③龙门山北段的河流双对数图呈直线形态,说明该区域达到均衡状态,处于均衡期;④龙门山不同地区的水系发育特征,表明龙门山中段和南段具有更强的构造活动性、更高的隆升速率,龙门山北段则具有较弱的构造活动性、较低的隆升速率,并反映了青藏高原东缘的隆升作用具有明显的空间差异性。
Located on the eastern edge of the Qinghai-Tibet Plateau, Longmenshan is both the steepest mountain range in the peripheral mountains of the Qinghai-Tibet Plateau and is also one of the areas where tectonic activity and landscape are most strongly shaped. Therefore, the area becomes an experimental field for studying the correlation between tectonic-geomorphological-water systems. Based on the ASTER GDEM data, the longitudinal profiles of 15 bedrock channels in the eastern margin of the Qinghai-Tibet Plateau were extracted. The longitudinal mathematical morphology of the river profiles was fitted by a simple mathematical function. Combined with the model of bedrock hydraulic erosion, the topographic features of Longmenshan were analyzed. The research obtains the following recognitions: (1) Through analyzing the longitudinal profile of the Longmenshan River, the Longmen Mountain has a high uplift rate as a whole, leading to strong river erosion in this area; (2) Of the river logarithmic graph above the main convex, indicating that the region has not yet reached an equilibrium state, in the pre-equilibrium period; ③ North Longmenshan river logarithmic graph showed a straight line shape, indicating that the region reached an equilibrium state, in a balanced period ; ④The water system development features in different parts of Longmen Mountains indicate that the middle and southern Longmenshan have stronger tectonic activity and higher uplift rate, and the northern Longmen Shan has weaker tectonic activity. The lower Longmen Ascertaining the uplift of the eastern edge of the Qinghai-Tibet Plateau has obvious spatial difference.