Rifting, intraplate magmatism, mineral systems and mantle dynamics in central-east Eurasia: An overview

The central-east Eurasia region comprising the Siberian Craton, the Central Asian Orogenic Belt, the Tarim and Sino-Korean cratonic blocks bordered by the Phanerozoic Tethysides, Qinling and SE Asian orogenic belts preserve important imprints of geodynamic processes associated with the formation of continental crust and associated mineral deposits, as well as the assembly and dispersal of supercontinents. From a comprehensive overview of the geologic, geochronologic and metallogenic history of Central-East Eurasia, as well as the recent conceptual models on plate and plume tectonics, we demonstrate that intraplate tectonics, particularly those driven by plumes, exerted an important control on mantle dynamics, magmatic pulses, and the formation of a variety of mineral systems of economic significance. Models of mantle dynamics that attempt to explain intraplate magmatism invoke mantle plumes, various forms of lithospheric delamination, slab roll-back, stagnant slab subduction and hot trans-lithospheric strike-slip fault zones. We confirm that many of the features previously ascribed to subduction-related systems could be well explained by post-collisional intracontinental and extensional settings suggesting that intraplate tectonics played a key role in the secular evolution of the magmatic and metallogenic systems in the Eurasian region.In this contribution, we provide an overview of the general geology and tectonic framework of central-east Eurasia, including the Siberian Craton, the western-Siberian Lowlands, the Central Asian Orogenic Belt (CAOB), and the Tarim–North China cratonic blocks. This is followed by a discussion and brief description of the rift systems and associated intraplate magmatism of central-east Eurasia, culminating with the giant Siberian rifts and large igneous province Lake Baikal rift system.We then describe a selection of mineral systems that are unquestionably attributed to intraplate tectono-magmatic processes. These mineral systems include: the Ni–Cu–PGE deposits of Noril'sk–Talnakh, Jinchuan, and those associated with zoned mafic–ultramafic intrusions in NW China, and alkaline–peralkaline complexes, carbonatites and kimberlites in Siberia. In the last part of the paper, we provide an overview of mantle dynamics, for which we consider mantle plumes arising from the core–mantle boundary, asthenospheric mantle upwellings due to delamination, lithospheric thinning and/or subduction slab break-off, asthenospheric upwellings due to flat slab settings and those related to translithospheric strike-slip tectonics.

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