Geochronological Atlas of Major Structural and Petrological Complexes of Russia is a continuously updated summary of determinations of the isotopic age of rocks, ores and minerals using U-Pb, Pb-Pb, Sm-Nd, Rb-Sr, Re-Os, K-Ar, Ar-Ar and other methods with geo-reference to mapped subdivisions of serial legends to the State Geological Maps-1000/3 and -200/2. The GIS resource contains results for the area of the Russian Federation obtained at the up-to-date analytical level at the VSEGEI Center of Isotope Research, as well as in other isotope laboratories, published in peer reviewed domestic and foreign periodicals since 2002. Geochronological data are accompanied by detailed petro logical and geochemical information. For the convenience of references to specific datings, the resource is also structured according to the years of new geochronological data acquisition (at present, at least 500 per year) in the form of annual geochronological bulletins of VSEGEI (for 2013–2022). To date, the Atlas database contains about 9000 relevant datings, of which about 70 % were obtained at the VSEGEI Center of Isotope Research and about 30 % at isotope laboratories of the Russian Academy of Sciences, universities and foreign centers.

The petrographic composition in the upper part of the Vuruchuaivench Massif section, the Monchegorsk layered complex, was studied. Samples from the surface and core samples from drilling wells to a depth of 280,1 m were taken for studying. The prevalence of secondary metasomatic minerals was identified in this part of the section. Plagioclase is the only primary igneous mineral found in the samples. Three associations and the sequence of metasomatic mineral crystallization are distinguished. Propylitization – α-, β-zoisites, clinozoisite and chlorite; beresitization – quartz, sericite, carbonate and sulfides; amphibolization – two generations of amphibole. The formation of amphiboles is a result of metasomatic crystallization rather then the replacement of primary magmatic pyroxene. PGE minerals are represented by arsenide, sulfoarsenide, and tellurobismuthide of platinum and palladium, which are associated only with secondary silicates.

Сalculations showed that atomic ratios of some Y-group rare earth elements such as Lu, Yb, Tm, Er, Ho, Dy, Tb, are statistically constant and do not depend on the type of rock, the place of their sampling, the REE cumulative concentration. The most variable are ratios of the Ce-group elements: La, Ce, Nd, Pr. It is suggested that variations in the index values of these elements can provide additional information concerning the geological or geochemical setting, the depth of the rock or its age.

Principles of the Precambrian stratigraphic subdivision are considered. It is shown that it is impossible to solve problems of the Upper Precambrian stratigraphy in Russia and adjacent countries by exclusively regional investigations. Precambrian fragment of the General Stratigraphic Scale (GSS) should have a chronostratigraphic framework, like the Phanerozoic Scale. The necessity of concentrating the efforts of specialists aimed primarily at improving the Precambrian GSS as a reference point for all researchers in the regions is substantiated. Particular attention is paid to the discussion of establishing the Riphean/Vendian boundary.

Specific features of oxidative epigenesis in the continental margin structure (CMS) in the south of the Russian Far East are described. The productivity of the epigenesis for hydrogenic uranium is estimated. Mesozoic-Cenozoic depressions of the region are represented as relict structures, an integral part of the Holocene orogenic system of the CMS. It is shown that all depressions were upthrown in the Holocene, deformed by upthrow-shift tectonics and eroded, with a cutoff of up to hundreds of meters. A model of uranium mineralization formation in the surface oxidation zone evolving at the incrementally decreasing front of areal erosion, is presented. The evidence is given that the high rate of erosion in the CMS and a number of other factors prevent the ore genesis in this zone. The compression, which is typical of the orogenic CMS system, caused the formation of an exfiltration regime in the groundwater of its depressions. This prevents the formation of large stratal oxidation zones in them. At the same time, the presence of local, uranium-productive stratal oxidation zones in relict paleovalleys is justified in the region. Features of the evolution of uranium-productive fractured infiltration systems are shown.

The Luktur granitoid complex of the Yurovka terrane is mainly composed of sub-alkali leucogranite, granite, and granosyenite with a subordinate occurrence of normal and alkali feldspar granite, as well as quartz syenite and monzonite. Granitoids are characterized by elevated alkalinity, potassium type of alkalinity, enrichment in REE, but in general, their geochemical features vary in a wide range; no differentiation trends are marked. The similarity of geochemical, Nd-Sr isotopic and U-Pb geochronological parameters of granitoids of the Luktur Complex and metavolcanics of the Yurovka Complex was identified. The Luktur granitoids resulted from the anathectic melting of variable Yurovka metamorphic lithologies. According to the parameters of Sm-Nd and Rb-Sr isotopic systems, the lower age limit of the formation of the crystalline basement of the Yurovka terrane is estimated to be 2300 Ma. The U-Pb (SHRIMP II) age based on zircon from the Luktur Complex was determined to be 1975 ± 36, 1969 ± 13 and 1964 ± 13 Ma. The combination of isotope, geochemical and geochronological data suggest that both Luktur granitoids and Yurovka metavolcanics were formed in the Paleoproterozoic. Thus, two terranes of different ages can be distinguished within the Okhotsk massif – Paleoarchean Kukhtui terrane and Paleoproterozoic Yurovka terrane.

The paper shows the possibility of identifying in old structural and stratigraphic unconformity zones in the shields of the Siberian Platform of “unconformity-type” deposits, similar to the Athabasca uranium province, based on a comparative historical and geological analysis of uranium ore formation within the Canadian Shield of the North American Platform, the Aldan and Anabar shields of the Siberian Platform. In order to increase uranium reserves of the Russian Federation by identifying large deposits with high-grade, contrasting ores, it is proposed to carry out regional predictive and metallogenic surveys for uranium in old structural and stratigraphic unconformity zones of the Aldan and Anabar shields.

The article provides a brief description of geological and structural features of several different types deposits of the Tien Shan in Kyrgyzstan, associated with the structures of thrust tectonics. Separate representatives of two structural subgroups are considered: deposits controlled by thrusts and fold-nappe structures. The first subgroup includes the Taldybulak Levoberezhny porphyry gold deposit (Northern Tien Shan) and the Kumtor gold deposit in carbonaceous shale (Middle Tien Shan). In the second subgroup, deposits of the Southern Tien Shan are characterized: gold-tungsten-tin deposits of the Sarydzhaz ore district and gold-mercury-antimony deposits of the Katran ore district.

The paper describes the historically formed Tokur gold mining center. It consists of the Malomyr, Verkhnyaya Stoiba, Tokur and Khargino ore and placer clusters of the Jagdy-Selemdzha metallogenic zone of the Amur gold province. Since 1918, about 127,2 tons of gold have been extracted from gold deposits of the center, mainly from the major Albyn, Tokur and Malomyr deposits. It is shown that the near-term perspectives of the Tokur center are associated with the development of the Elgin and Albyn fields. A list of gold prospects is given; their additional appraisal can result in the identification of new economic ore gold deposits.