UHP rocks and the Dabieshan Orogenic Belt
The Dabieshan Orogenic Belt, which contains ultra-high-pressure (UHP) metamorphic rocks, is the Mesozoic collision zone between the Sino-Korean and Yangtze cratons. With respect to the exhumation of the UHP rocks, the Dabieshan Orogenic Belt can be divided into four units, i.e. allochthonous, parautochthonous, autochthonous and reworked units. The allochthonous unit is composed of UHP rocks. The parautochthonous unit is represented by the non-UHP rocks of the Yangtze sedimentary cover and crystalline basement, as well as an accretionary wedge. The autochthonous unit includes Jurassic and Cretaceous sedimentary and igneous rocks. The reworked unit is characterized by migmatization. The deep structure of the Dabieshan Orogenic Belt is characterized by a Moho offset and dome structure in the middle and upper crust, as recording a compressional state. A northward subduction of the Yangtze craton is evidenced by geological, geophysical and geochemical data. In the formation of the Dabieshan orogenic belt, a precondition is the low density of the subducted continental materials. If the UHP unit is the piston to build up the orogenic belt, then the continuous compression between the Sino-Korean and Yangtze cratons is the motor to trigger the mountain-building processes.
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Aspects of the Tectonic Evolution of China
The subject of this Special Publication is one of the most interesting in global geoscience, the tectonic evolution of China. The assemblage of terranes that underlie this part of the world provides outstanding opportunities to elucidate global processes, and many of the factors that shape the Earth's lithosphere are best exemplified by the geology of China and its immediately adjacent areas
In addition, there are geological features that are particular and unique to the region. Some have been the focus of recent attention and have attracted international interest because of their global importance. This volume provides accounts of up-to-date research by Chinese and international geological teams on key aspects of the tectonic evolution of China and its surrounding areas. The papers describe the formation of the geological terranes that make up this part of east Asia, place constraints on plate tectonic models for their assembly and provide accounts of unique geological feature of the subcontinent.