Минеральные ассоциации золоторудных проявлений Берентальского рудного поля (Северо-Восток России)

Abstract

Berental prospective ore cluster (Magadan region) hosts a many ore occurrences, which differ in mineral composition, ore productivity, features of secondary and primary dispersion halos. As a result of the study of ores, mineral associations have been characterized, the stages of formation of ore occurrences and the alteration of the ore cluster have been established. The interrelation of five genetic types of native gold with mineral associations is revealed. Key ore occurrences have formed during several stages of ore formation associated with the evolution of a common hydro-thermal system. The earliest mineral association (arsenopyrite-lellingite), which contains the first generation of gold, was formed in the quartz-sericite facies in marginal parts of Berental stock and refers to the lower level of erosion truncation. After that, arsenopyrite-telluride association was formed in the marginal granites and arsenopyrite-galenobismutite association was formed in the exomorfic zone, they contain gold of the second - fourth generations with signs of recrystallization and diffusion transformations. Arsenopyrite-silver and pyrite-silver ore associations are localized at the upper level of the erosion trancation in calcium-containing birch with quartz veins, these associations contain low-fineness gold of the fourth and fifth generations. Pay gold mineralization of the Berental ore field is associated with arsenopyrite-telluride and arsenopyrite-galenobismutite associations, contains gold with a fineness of 750-945 %. The spatial placement of mineral associations is consistent with the placement of secondary and prima-ry scattering halos: complex Au-Bi-As halos accompany arsenopyrite-lellingite, arsenopyrite-telluride and arsenopy-rite-galenobismutite associations; for Au-As-Ag and Au-Ag-Pb-Zn association there is a spatial conjugation with ar-senopyrite-silver and pyrite-silver associations, respectively.