Characteristics and genesis of the Mnogovershinnoe gold-silver deposit, SE Russia

Abstract

The Mnogovershinnoe ore deposit is part of the Bekchiul volcano-plutonic complex, located on the northern flank of the East-Sikhote-Alinsky belt in SE Russia. The complex was developed in two stages during the Senonian (Upper Cretaceous) and Paleocene-Eocene. The early stage is represented by a poorly differentiated andesite-granodiorite association and the late stage is marked by subalkaline monzodiorite-granite intrusions. The vein-metasomatic zones with Au-Ag mineralization are associated with magmatic units of the early stage and are crosscut by large dikes of the late stage. The deposit shows features of epithermal mineralization and a higher temperature overprint. The total ca. 1000 m zone of productive mineralization shows vertical zoning characterized by gold-sulfosalt-sulfide, gold-sulfide, then gold-telluride-sulfide, and telluride-sulfide, from bottom to top. The hydrothermal system of the deposit shows evidence for mixing between fluids derived from the volcano-plutonic units and meteoric water. The mineralization is inferred to have formed from the mixing between these fluids and by the fluctuations of fluid pressure in the system.