Abstract Along the lower reaches of the Yarlung Zangbo River, scattered alluvium sections appear on T1 and T2 terraces. The alluvial deposits on the T1 terrace in Linduo and Ximogou and the T2 terrace in Guoguotang are composed principally of coarse-grained sand particles and rock fragments, with no observable fine-grained components. The T1 terrace alluvium section is dominated by clay and silt and occurs near the town of Dexing, and optically stimulated luminescence dating of sample from this site revealed an age of 18.2 kyear, which indicates that the incision rate of the Yarlung Zangbo River has been 4.7 mm/year since the formation of this section. On the basis of the component characteristics of terraces in Motuo County, the provenance for the terraces is probably related to the breaking of the palaeo-dammed lakes in the middle reaches of the Yarlung Zangbo River. A 430 m elevation difference still exists between the study area and the local base level downstream of the Yalung Zangbo River (Assam Plain), although this river has a strong incision capability (4.7 mm/year), which suggests that tectonic uplift remains very intense east of the Namche Barwa syntaxis.

中文翻译：

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南池巴瓦以东雅鲁藏布江下游阶地特征及下切速率：对构造抬升的制约

摘要 在雅鲁藏布江下游，T1、T2阶地出现零星的冲积层。林多、西磨沟T1阶地和果果塘T2阶地的冲积沉积物以粗粒砂粒和岩屑为主，未见细粒组分。T1阶地冲积层段以粘土和粉砂为主，产于德兴镇附近，该遗址样品光激发光测年显示年龄为18.2 kyear，表明雅鲁藏布江的切入率为4.7自本节形成以来的毫米/年。根据墨脱县梯田的组成特征，梯田的来源可能与雅鲁藏布江中游古堰塞湖的破裂有关。研究区与雅鲁藏布江（阿萨姆平原）下游当地基准面仍存在430 m的高差，但该河流具有较强的切割能力（4.7 mm/年），表明构造隆升仍然非常强烈Namche Barwa 语法结构以东。