Mesozoic granitoid types and metallogeny of the East China Circum-Pacific continental margin

This paper synthesizes the geotectonic background, genetic types and metall ogenetic relations of the Mesozoic granitoids in the East China continental margin. By the Mesozoic, the Siberia Plate, North China Plate and South Ch ina Plate amalgamated together, resulting in formation of a unified Eurasia super-continent. Since the late Triassic to early Jurassic period, the ter ritory of East China gradually became a Cordilleran style active continenta l margin. During the Jurassic to early Cretaceous (early to middle episodes of Yanshanian orogeny), the Paleo-Pacific plate strongly collided with and subducted under the Eurasia continent, reactivated the consolidated East C hina continental margin. The granitoids of both transformation series and s yntexis series were generated. Many granitoid-related large and giant metal deposits were formed. Furthermore, the W, Sn, Be, Nb, Ta and U mineralizat ions are mostly associated with the transformation series; while the Fe, Cu , Mo and Au mineralizations are mostly associated with the syntexis series. The late Yanshanian orogeny (late Cretaceous) began a transition to the we stern Pacific style continental margin. A tensional environment resulted in development of alkaline granitoids and formation of continental red basins . The Cenozoic orogeny was characterized by a backarc spreading and rifting regime in this region.