Abstract:

The evolution of Tibet Plateau is the most magnificent geodynamic movement and the most important geological event, which influenced fundamentally nearly all fields in geology. Its impact extended to a broad range, causing the direct response of Southeast Asia and Middle Asia and forming the broad Himalayan tectonic domain, which further affected South Asian, West Asian, North Asia and their boundary sea areas. The entirety of these regions is called the TibetHimalayan tectonic domain. In terms of its impact to the neighbor areas, the evolution of Tibet Plateau can be divided into three stages, including the soft collision stage between Indian plate and Eurasian plate and the hard collision stages of early intracontinental joined and late relatively integrated deformation in the Tibet area. The influence of soft collision (6044 Ma) was mainly in and near Yarlung Zangbo Suture Zone. The structural deformation, magmatic activities, metamorphic process and mineralization in the early intracontinental joined stage of hard collision (4422±2 Ma) occurred in Tibet and its edges, which only influenced the broad neighbor areas locally through huge and deep strikeslip faults. During the late stage of hard collision (22±2 Ma to now), the massifs in the area of the present Tibet Plateau underwent strong shortening by compression and joined. When these massifs were assembled and welded into a relatively integrated block, the evolution entered the third stage of relatively totally deformed in the Tibet area. The further collision of Indian plate and Eurasian plate, the main geologic events and deep geologic process in the Tibet Plateau began to influence surrounding terrains obviously. The period of the End Oligocene to the Early Miocene (20±24 Ma) is the important turning period in the evolution of Tibet Plateau. The structural deformation, sedimentary deposit, magmatic activities, metamorphic process and mineralization in Tibet Plateau have evident difference before and after the turning periods, which shows the great change of the geodynamic environment around the turning period. Then the Tibet Plateau started the relatively integrated movement and deformation stage and its influences to the mountain uplift and basin subsidence, to the concentration and dissipation of mineral deposits, and environmental changes were remarkable and increasing with time, which caused the episodic spreading and developing of the TibetHimalayan tectonic domain. The correlation between the regional structures and strata of Tibet Plateau and  EastSoutheast Asia indicates that the dynamic source of the important change in geodynamic environment of the Tibet Plateau was not limited to the inner area of the plateau but with a broad regional geodynamic background.

Key words: Key words: Tibet Plateau; TibetHimalayan tectonic domain; evolution stage; turning period; records of surrounding areas; spacetime coordinate