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Using the high-precision technique of MC-ICP mass spectrometry, the isotope composition of lead was studied for the first time in sulfides of different mineral associations at the Verninskoe deposit that belong to large gold deposits of the Lena Province. In 23 monofractions of sulfides (pyrite, arsenopyrite, galena, and sphalerite), the Pb-Pb data showed a pronounced heterogeneity of the isotope composition of ore lead (Pb/Pb = 18.21-18.69, Pb/Pb = 15.59-15.67, and Pb/Pb = 37.98-38.63) for the deposit as a whole. This heterogeneity is also seen to a lesser degree within individual samples. In this case, a correlation takes place between the isotope composition of ore Pb and the type of mineral association: the sulfides in earlier associations are characterized by lower contents of the Pb, Pb, and Pb radiogenic isotopes compared to the minerals of later parageneses. The comparison of Pb-Pb isotope characteristics of ore mineralization of the Verninskoe deposit to those of the Sukhoi Log deposit (the greatest in the Lena Province) testifies to the geochemical similarity of the sources of ore Pb involved in the formation of these deposits. The sources as such were terrigenous rocks of the Bodaibo synclinorium formed mainly as a result of the disintegration of Precambrian rocks of the Siberian craton. [ABSTRACT FROM AUTHOR]

The article presents study which investigates the isotope and age geochemistry of ore-hosting granodiorites of the Nyal'm-1 gold deposit at Kola Peninsula, Russia. It says that the Archean greenstone belts (GSBs) are localized in Paleoproterozoic volcanogenic-sedimentary complexes and are linked to the ore-metasomatic procedures in areas of shift deformations. It states that the investigation was done with the use of modern local isotope geochemical methods, along with the description of geological composition and structure of the volcanogenic-sedimentary complex of the GSB Kolmozero-Voron'ya (KV). Conclusion suggests that the age and genetic relationship of gold deposits enables the reconsideration of the concepts of the age of the gold formation.