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The Central Asian supercollage hosts metamorphic, turbidite, and island arc superterranes, as well as overlapping magmatic arcs and sedimentary basins, spanning 1,000 Ma from Mesoproterozoic to early Mesozoic times. They constitute Baikalides, Timanides, Uralides, Altaids, and Mongolides, framed by Siberian, Eastern Europe, Arctic, Tarim and North China cratons.
It is suggested that these cratons formed a single cratonic mass within the supercontinent Rodinia. After breakup of Rodinia via propagation of the Proto-Pacific spreading centres between Siberia and, possibly, Australia, the Central Asian history can be explained through translation of Siberia from Laurentia towards Eastern Europe. This translation was probably universally responsible for the initial separation of the Mesoproterozoic superterranes from adjacent Siberia and Eastern Europe cratons and their further fragmentation into multiple arc-backarc oceanic systems with large-scale oroclinal bending.
In Neoproterozoic to Early Cambrian times, the initially single magmatic arc (Kipchak and Tuva-Mongol) produced significant base metal deposits of VMS and possible Sedex styles, found in Altai-Sayan and Central Kazakhstan areas. In Late Cambrian to Middle Ordovician times, these arcs were separated due to intra-arc spreading into the Great Steppe magmatic arc in Kazakhstan with Au-Cu porphyry deposits, whereas in the Mongolides, a new Khentyi magmatic arc started to form in Central Mongolia. In the Late Ordovician, these reorganisations culminated in emplacement of large intrusion-hosted gold deposits, forming three subprovinces in northern Kazakhstan, Kuznetsk Alatau and Eastern Sayan.
In middle Paleozoic to early Mesozoic times, older terranes were stitched by Kazakh-Mongol, Valerianovka-Beltau-Kurama and Orkhon-Selenga arcs, each hosting superlarge Au-Cu porphyry (Oyu-Tolgoi, Kounrad, Kalmakyr, Erdenet) and large VMS deposits (Rudny Altai), as well as some of the world's largest Pb-Zn and Cu deposits in the backarc sedimentary basins. At the same time, a new immature Urals-Zharma arc, hosting world's best preserved Cu-VMS deposits in the Magnitogorsk terrane, was initiated.
By end-Paleozoic, Siberia completed its journey towards Eastern Europe, with multiple collisions of the newly-formed arcs, coinciding with formation of the world's largest orogenic gold systems in the Tien Shan, Urals, eastern Kazakhstan and Lena-Bodaibo areas.
The final episode relates to the oroclinal bending and collision of the Mongolide terranes between Siberia and North China cratons in the early Mesozoic. It produced some medium-size orogenic gold deposits in the Mongol-Okhotsk suture, and the supercollage became stitched by the Yanshanian magmatic arcs, hosting large epithermal deposits in Transbaikalia, evolutionally related to the Circum-Pacific tectonism.
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