Th and U Minerals in Adakites as Indicators of Post-Collision Processes in the Stanovoi Cratonic Superterrane (Russian Far East)

Early Cretaceous post-collision adakites of the Stanovoi Superrterrane (Russian Far East) are geochemically similar to adakites associated with slab break-off in collision and post-collision settings. They contain Th, U, Ag, and Au microminerals in assemblage with amphibole, biotite, feldspars, zircon, apatite, monazite, rutile, F-bearing titanite, zirconolite, ilmenite, and magnetite. Structural peculiarities and composition of these microinclusions indicate their crystallization from adakitic melts derived from crustal magmatic sources, which are affected by the interaction of deep high-temperature F‒P‒Ti‒Zr‒Th‒U‒REE fluids with sulfide-rich mafic crust of large collision structures. It is concluded that the adakites with such microminerals can be indicators of post-collision processes, which are able to produce deposits of rare and strategic metals within collision margins of the Precambrian cratons.