Propagation of surface uplift, lower crustal flow, and Cenozoic tectonics of the southeast margin of the Tibetan Plateau
Propagation of surface uplift, lower crustal flow, and Cenozoic tectonics of the southeast margin of the Tibetan Plateau
复制标题
DOI：
10.1130/g22679.1
复制
发表时间：
2006-10-01
期刊：
影响因子：
5.8
通讯作者：
Chen Liangzhong
中科院分区：
文献类型：
--
作者：
Schoenbohm, Lindsay M.;Burchfiel, B. Clark;Chen Liangzhong
青藏高原东南缘的地表隆起被解释为从西北部靠近西藏边境的地方向东南方向，在云南省中部的红河地区，中国说。这一解释是基于现有的热年代学数据和新的填图、沉积学和古植物学数据，证明在上新世或更晚的时候在红河源头发生了切割。与以前公布的地表隆升和地壳厚度梯度的数据一起，这是青藏高原东南缘通过下地壳流生长的有力证据。哀牢山-红河剪切带的位移在上新世早期减缓或停止，鲜水河-小江断裂系统启动，适应了围绕东喜马拉雅构造的扩散变形和旋转。我们认为，形变方式的改变与通过下部地壳流动引入的弱地壳层之间存在运动学联系。
Surface uplift of the southeast margin of the Tibetan Plateau is interpreted to have progressed from the northwest, near the Tibetan border, to the southeast, in the Red River region of the central Yunnan Province, China. This interpretation is based on existing thermochronologic data and new mapping and sedimentologic and paleobotanic data demonstrating incision in the headwaters of the Red River in Pliocene time or later. Together with previously published data demonstrating surface uplift and a gradient in crustal thickness in the absence of upper crustal shortening, this is strong evidence for growth of the southeast margin of the Tibetan Plateau through lower crustal flow. Displacement along the Ailao Shan-Red River shear zone slowed or ceased in early Pliocene time, and the Xianshuihe-Xiaojiang fault system initiated, accommodating diffuse deformation and rotation around the Eastern Himalayan syntaxis. We suggest a kinematic link between the change in mode of deformation and the introduction of a weak crustal layer through lower crustal flow.