Magmatic–Fluid System of the Vysokogorskoe Porphyry Tin Deposit (Sikhote-Alin, Kavalerovo Ore District, Primorsky Krai, Russia): a Magmatic Stage

Abstract

Inclusions of the mineral-forming media in quartz of the Vysokogorskoe deposit are studied in detail. The compositions of the melts correspond to peraluminous potassium granites of normal alkalinity, depleted in rare alkalis, F, and Cl. The water content in the melts reached 7–9 wt %; CO2 and CH4 were also important in mineralizing fluids. Quartz crystallized at 620–650°C. Assemblages of four types have been identified as primary fluid inclusions: (1) inclusions of carbonate or sulfate aqueous solutions coexisting with melt inclusions, (2) low-density vapor-dominated primarily magmatic inclusions, (3) presumably postmagmatic low-salinity aqueous and vapor-dominated inclusions, and (4) multiphase fluid inclusions associated with vapor-dominated ones also formed at the postmagmatic stage. Daughter pyrosmalite–(Fe) and hibbingite, which was found for the first time in inclusions from quartz of the Vysokogorskoe deposit, made it possible to characterize the solutions as high-salinity chloride Na/K and Fe2+. Presumably, those solutions may have been the most efficient in Sn transport during the formation of fluid–explosive breccias and vein mineralization of the Vysokogorskoe deposit. The magma chamber itself most likely served as a heat source and, to a large extent, a source of aqueous fluid for the hydrothermal system of the deposit.