A new Research Project on the Dynamic Processes beneath the Northern Tibetan Plateau.

We present a new Sino-German cooperation project in the northern Tibetan plateau:Unraveling the Dynamic Processes beneath the Northern Tibetan Plateau - PaleozoicCollision and Cenozoic Destruction of Mantle Lithosphere and Plateau Uplift. The project isfunded by the German Research Foundation (DFG) and the National Natural ScienceFoundation of China (NSFC) and involves seismic experiments as well as data analysis. Theproject aims to study fundamental questions on plateau building, processes that modify anddestroy continental lithosphere and which control lithospheric dynamics beneath orogenicbelts. The northern Tibetan Plateau features widespread Cenozoic volcanism. While themultiple terranes that constitute the Tibetan plateau become older from south to north, themagmatic events within the plateau become younger from south to north. This indicates morerecent tectonic acitivity in the northern Tibetan plateau, which is in fact expanding towardsNortheast. Seismic observations beneath Northern Tibet show poor Sn wave propagation andlow Pn wave velocities, while the shallow mantle shows low seismic velocities and strongseismic anisotropy. What is causative for those observation and what is the mode and mechanism of uplift inNorthern Tibet? Is it either caused by thickening of the Indian and Eurasian mantlelithosphere or are those observations rather explained by removal of Eurasian mantlelithosphere? What is the extend of the Indian plate beneath Tibet? Does a gap betweenIndian and Eurasian mantle lithosphere exist or do they meet beneath northernTibet? Northern Tibet is constituted of the Hoh Xil Songpan-Ganzi and the NorthQingtang terranes, which collided in the Triassic (around 250 Ma). What is thesubduction polarity of the Paleozoic Tethys ocean separating both terannes? Is theTriassic fault reactivated in Cenocoic as indicated by a Moho jump at the faultlocation? To tackle those questions we plan to deploy and analyze two linear passive-source seismicarrays in northeastern Tibet as well as to include in our analysis data from the temporalTITAN deployments, that have been conducted in Tibet from 2008 to today. Toresolve the crustal and upper mantle structure of the area we are performing surfacewave tomography using ambient noise and earthquakes and plan to jointly invertthem with receiver functions. We will present a project overview as well as firstresults. [ABSTRACT FROM AUTHOR]