Magmatic–Hydrothermal Transport of Metals at Arc Plutonic Roots: Insights from the Ildeus Mafic–Ultramafic Complex, Stanovoy Suture Zone (Russian Far East)

The Ildeus mafic–ultramafic complex represents plutonic roots of a Triassic magmatic arc tectonically emplaced into the thickened uppermost crust beneath Mesozoic Stanovoy collided margin. cumulates host Ni-Co-Cu-Pt-Ag-Au sulfide-native metal-alloy mineralization produced through differentiation subduction-related primary mafic melt. This melt was sourced in metal-rich sub-arc mantle wedge hybridized by reduced high-temperature H-S-Cl fluids and slab/sediment-derived siliceous melts carrying significant amounts Pt, W, Au, Ag, Cu Zn. Plutonic rocks experienced pervasive later-stage metasomatic upgrade sulfide–native metal–alloy assemblage presence oxidized hydrothermal fluid enriched sulfate chlorine. new formed shallow epithermal environment includes native gold, Ag-Au, Cu-Ag Cu-Ag-Au alloys, heazlewoodite, digenite, chalcocite, cassiterite, galena, sphalerite, acanthite, composite Cu-Zn-Pb-Fe sulfides, Sb-As-Se sulfosalts Pb-Ag tellurides. A two-stage model for magmatic–hydrothermal transport some siderophile (W, Au) chalcophile (Cu, Zn, Ag) metals subduction–collision environments is proposed.