Relation of Tethys Ocean Subduction, Collision and Closure with Regional Metamorphism, Volcanism and Mineralization Exemplified on the Eurasian Active Margin

The geodynamic development of Eurasian active margin is related to subduction, collision and closure of Tethys Ocean.It is divided on pre-collision and post-collision stages.The pre-collision development controlled by subduction, whereas post-collision related by orogenesis, granodiorite magmatism gold base and trace metals (Sb,W, Mo and Hg) metallogeny.The mentioned trace metals association is the geochemical indicator of first stage of post-collision development.The second stage revealed in andesite basalt, shoshonite, olivine basalt and tholeiite volcanic activity.Pre-collision stage is controlled by steady state subduction related with metamorphism and calc-alkaline volcanic activity in subaqual and island conditions of island arc setting.It is lately with steepening of subducting slab and incursion of mantle diapir transferred in interarc-backarc and minor ocean setting with shoshonite-trachyandesite and alkali olivine basalt and tholeiite volcanism and later with ophiolite volcanism, dunite-peridotite magmatism and Cu-pyrite mineralization of minor ocean setting.The pre-collision stage is developed temporally and spacially along dipping of subducted slab in the island arc setting transferring in the backarc-interarc and minor ocean settings.The similar transferring occurs laterally to dipping of slab and ascending succession.The alternation of settings shown the cycling along dipping spatial and temporal alternation of island arc, backarc and minor ocean settings.Laterally to dipping alternation is only spatial, whereas in ascending succession cycling is only temporal, localized spacially.The pre-collision development occurs in subaqual condition, whereas related to orogenesis post-collision development is mainly subaerial.