The Qing-Tibet Plateau has long been known as the natural geological museum. the golden key to the global orogenic mechanism, the natural laboratory for the continental dynamics theory, and the pulser of the global changes, which is the important source region and the competition field deriving new theories, knowledge and discoveries.Numerous orogenic belts were developed in the middle and western parts of China, the Qinghai-Tibet Plateau are the most distinctive, with rich and varied geological phenomena. The eastern margin of the Plateau lies in the significant position of the Chinese tectonic units, which is located in the transition zone between the mantle depression in the southern region (the Qinghai-Tibet region) of west part of China and the deep structure of the middle part, and in the eastern section of the Helansan—Longmenshan steep-change belt which passes obliquely through the margin. The northwestern region of this zone is characterized by the thick Crust as well as the thick Mantle, and the southeastern, by the thin Crust as well as the thin Mantle of the Sichuan basin. Distinguished nonuniformities occur both in the vertical and horizontal lithosphere. A number of deep faults were developed in the zone, of which the Longmenshan lithospheric fault and the Xianshuihe fault belts are the most important. In the regional geology, the complete tectonic pattern is composed of five units, from the northwest towards the southeast:(1) The Songpan-Ganzi orogenic belt.(2) The Xianshuihe fault belt.(3) The Longmenshan thrust belt.(4) The foreland basin.(5) The foreland upwarp. The Xianshuihe fault belt, the Songpan-Ganzi orogenic belt, the Longmenshan thrust belt, and the foreland basin are the regional units unique to the eastern margin of the Qinghai-Tibet Plateau, and are the treasure of geoscience.It is not only the typical region to study the geodynamic processes between the Plateau and the periphery basins (the basin motivity), but the key position to verify if the Plateau is derived from the crustal thickening or from the extrusion by the sinistral rotation to absorb the northward diapirism of the Indian continent after the collision between Indian and Asian continents; it is also the critical region to conduct investigations into the change in climate, hydrographic net, and ecological environment of the middle and upper reaches of the Yangtze River. The margin spans the Qinghai-Tibet Plateau, the Longmenshan mid-high mountain, and the piedmont alluvial plain, which covers the relatively developed economic region (including Pengzhou City, Dujiangyan City, and Yaan Prefecture) of the Chengdu Plain, and the underdeveloped region of the Aba and the Ganzi Tibetan autonomous prefectures. There are gaps between the two regions in economics, natural form, traffic, and human geography. During the recent years, a number of overseas geoscientists from USA (MIT, CIT etc), UK, France, Swithzerland, Australia, Japan, and Germany took field trips to the region and were involved in some research projects to varying extent .
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