Formation of the Tibetan Plateau during the India-Eurasia Convergence:Insight from 3-D Multi-Terrane Thermomechanical Modeling  

作　　者：Jile Chen Peimin Zhu Yuefeng Yuan Guifan Chen 

机构地区：[1]School of Geophysics and Geomatics,China University of Geosciences,Wuhan 430074,China [2]Geothermal Engineering Research Center,Three Gorges Geotechnical Consultants Co.,Ltd.,Wuhan 430074,China

出　　处：《Journal of Earth Science》2024年第1期112-130,共19页地球科学学刊（英文版）

基　　金：sponsored by the National Key R&D Program of China(No.2021YFA0715100);the Shenzhen Fundamental Research Program,China(No.JCYJ20220818102601004);the National Natural Science Foundation of China(No.41774145);the Pre-research Project on Civil Aerospace Technologies(No.D020101)of CNSA。

摘　　要：Various models exist to explain the formation of the Tibetan Plateau,including“tectonic escape”,“pure shear thickening”,“convective removal of the lithospheric mantle”,and“lower crustal flow”model.The first two models are primarily constructed on pure mechanical models but are unable to reasonably explain the tension and shear phenomena inside the plateau.The latter two are rheological dynamic models based on deep geophysical observations.However,the spatial range of the lower crustal flow and its role in the plateau formation/uplift remain controversial.Five multi-terrane viscoplastic thermomechanical models were constructed to simulate the uplift and lithospheric structure change of the Tibetan Plateau during the post-collision stage(since 35 Ma)under the convergence of the Indian Plate.Results show that the plateau's formation begins with crustal thickening,blocked by strong terranes at the northern plateau,and expanded laterally to the east.The lithosphere thickens gradually and experiences delamination at its base,elevating temperature within the crust and forming partial melting layers in the central plateau.As convergence persists on the southern side,the northern plateau's lithosphere bends downward and undergoes delamination,further heating the crust and promoting the northward and eastward flow of partial melting layers,leading to secondary uplift around the plateau.

关 键 词：3-D thermomechanical modeling Tibetan Plateau plateau uplift crustal flow 

分 类 号：P542[天文地球—构造地质学]