雅鲁藏布江大拐弯地区河流形态特征及其意义  

The morphology of the Yalung Zangbo River in the Great Canyon Region and its implications

作　　者：黄文星[1,2,3] 王国灿[1,2] 王岸[1,2] 曹树钊[1,2] 曹凯[1,2] 

机构地区：[1]中国地质大学地质过程与矿产资源国家重点实验室,湖北武汉430074 [2]中国地质大学地球科学学院,湖北武汉430074 [3]广州海洋地质调查局,广东广州510760

出　　处：《地质通报》2013年第1期130-140,共11页Geological Bulletin of China

基　　金：国家自然科学基金项目<中新世以来高喜马拉雅岩石剥露与地表气候-构造响应研究>(批准号:40902060);中国地质调查局项目<青藏高原新近纪隆升过程与地质事件群研究>(编号:1212011121261);<青藏高原新生代地质作用过程与第四纪环境演变综合研究>(编号:1212010610103)

摘　　要：为探讨雅鲁藏布江大拐弯地区区域隆升的特点,通过DEM(数字高程模型)和遥感影像提取雅鲁藏布江干流和帕隆藏布江的形态特征,引入Hack剖面、SL参数和Amos河宽理论模型进行分析。雅鲁藏布江干流在大渡卡以下河段的Hack剖面表现为上凸形态,SL参数升高、河流宽度减小,在藏布巴东瀑布-雅鲁藏布江大拐弯顶端段,SL参数达到最大值,河流宽度达到最小值;大拐弯顶端以下河段,SL参数减小,河流渐宽。帕隆藏布江古乡以下河段SL参数梯级增高,河流宽度总体收窄,大拐弯顶端附近达到最大值。综合2条河流的地貌特征和区域地质与地理背景,认为雅鲁藏布江大拐弯地区的隆升具有不均一性,雅鲁藏布江在大渡卡附近开始进入快速隆升区段,隆升最强烈的区段位于藏布巴东瀑布-大拐弯顶端段,大拐弯顶端之后雅鲁藏布江逐渐远离隆升中心区。In order to probe into the features of uplift in the Great Canyon Region of the Yalung Zangbo River, the authors extract- ed the morphologies of the Yalung Zangbo River and the Parlung Zangbo River from DEM and remote sensing images, and analyzed them by adopting Hack profile, SL index and the model of Amos fiver width. The Hack profile of the Yalung Zangbo River which is below Datogka area assumes a convex shape. In this area, the SL index increases and the width of the fiver decreases. In the Tibet Bubba East Falls, the top of the Great Canyon, the SL index reaches the maximum while the width of the fiver reaches the minimum. In the fiver which is below the top of the Great Canyon, the SL index decreases whereas its width becomes wider. In the Parlung Zangbo River which is below Guxiang Village, the SL index increases whereas the width of the fiver decreases. Combined with the morphology of the two rivers and the regional geological and geographical background, the authors hold that the uplift of the Brahmaputra Great Bend area was heterogeneous, which entered the section with dramatically increasing uplift near Datogka area. The segment which had the strongest uplift is in the possession of Bubba East Falls, the top of the Great Canyon, and after that the Yalung Zangbo River was gradually away from the central area of the uplift.

关 键 词：雅鲁藏布江大拐弯 Hack剖面 SL参数 河流宽度 隆升 

分 类 号：P343.1[天文地球—水文科学]