Tibetan Plateau Formation: tracing material flow around the East-Himalayan syntaxis

关键的方面，如印度-亚洲碰撞的时间和性质，以及青藏高原高度和宽度的起源和演变，都是有争议的、未经检验的或未知的。认为青藏高原东部中新世至近代的地质、大地测量、古地磁、地貌和地球物理特征最好用中下地壳内低粘度物质的流动来解释；该模型与经典的岩石圈块体向东南亚大规模位移的逃逸模型形成对比。这两种模式对地壳流变学、岩石圈的垂直耦合以及高原的形成和生长都具有重要意义。在这里，我们通过研究东喜马拉雅合带（西藏东南部、云南西部）周围的热、力学变化和物质流动的几何形状、时间和强度来检验这些大陆岩石圈变形的基本模型。这个跨学科项目将与ITP的同事密切合作，整合来自地质学（结构几何、运动学、流变学、深度-温度-时间历史）、古地磁学（地壳块体旋转的程度和分布）和遥感/构造地貌学（反映当前变形的排水发育和河流捕获）的数据。

Critical aspects such as the timing and nature of India-Asia collision and the initiation and evolution of the height and width of the Tibetan Plateau are disputed, untested, or unknown. It has been argued that Miocene to Recent geologic, geodetic, paleomagnetic, geomorphic, and geophysical features of the eastern Plateau are best explained by flow of low-viscosity material within the middle-lower crust; this model contrasts with the classic escape model that calls for large-scale displacement of lithospheric blocks toward SE-Asia. Both models have fundamental implications for crustal rheology, vertical coupling in the lithosphere, and Plateau formation and growth. Here, we test these fundamental models of continental lithosphere deformation by studying the geometry, timing, and magnitude of thermal and mechanical changes and material flow around the E-Himalayan syntaxis (SE-Tibet, W-Yunnan). This interdisciplinary project will integrate, in close cooperation with ITP colleagues, data from geology (structural geometry, kinematics, rheology, depth-temperature-time histories), paleomagne-tism (degree and distribution of crustal block rotation), and remote sensing/tectonic geomorphology (drainage development and river capture reflecting current deformation).