Precambrian tectonic evolution of the North China Craton
The North China Craton (NCC) is a major Archaean craton, covering an area of c.300 000 km2 in north and northeast China. Almost all Archaean rocks on the craton experienced high-grade metamorphism and strong migmatization, so that the preserved greenstone belts underwent granulite-amphibolite-facies metamorphism, anatectic melting and strong deformation. This suggests that the NCC may have a more complicated early tectonic history than most other cratonic nuclei. The oldest NCC rocks are 3.8 Ga granitic gneisses in NE China and supracrustal rocks in eastern Hebei. Major continental growth occurred at 2.9–2.7 Ga. Two subsequent high-grade metamorphic events occurred at 2.6–2.45 Ga (‘2.5 Ga event’) and 1.9–1.75 Ga (‘1.8 Ga event’). The older episode is considered to mark an amalgamation event, whereas the 1.8 Ga event represents the final cratonization of the NCC. Some researchers have divided the 1.8 Ga event into a 1.9–1.8 Ga metamorphic event (interpreted as a continent-continent collision) followed by a 1.8–1.65 Ga rifting episode. Other workers have suggested that the metamorphism and rifting could be parts of a single tectonic event related to Palaeo-Mesoproterozoic mantle upwelling. The general consensus on the NCC for the period 2.5–1.8 Ga is that the craton was then in an inactive stage. However, in this paper it is proposed that several Palaeoproterozoic mobile belts existed (showing many of the characteristics of Phanerozoic orogens). During the Mesoproterozoic–Neoproterozoic, a set of sedimentary sequences (the Changcheng-Jixian-Qingbaikou systems) constituted a disconformable-pseudoconformable succession within an intra-cratonic aulacogen. The signature of a 1.4–0.9 Ga orogen and the Rodinia breakup is very weak, indicating that the NCC did not experience major deformation as it was amalgamated into the Rodinia supercontinent.
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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.