According to the results of magnetotelluric sounding under ore bodies of Ozernoe pyrite- polymetallic deposit revealed a linear zone of low resistivity rocks, which can be traced to a depth of 10 km and can be regarded as structure of feeder fluid. The presence of deep roots in pyrite ore deposits of the Ozernoe deposit is not consistent with existing understanding of its affinity to outliers Early Paleozoic volcanic-sedimentary rocks in the sag of the roof of the Angara-Vitim batholith.
The main objects of the research were the deposits of noble and non-ferrous metals of the Urals, Siberia and Novaya Zemlya. It is shown that the study of the variability of the material composition and stereometric features of ores (with computer modeling of the most important types of mineral aggregates) in the geological space is extremely important to reduce losses of useful components, predict the technological properties of mineral raw materials and identify the conditions of ore formation.
The main objects of the research were the deposits of noble and non-ferrous metals of the Urals, Siberia and Novaya Zemlya. It is shown that the establishment of a pomineral balance of distribution of chemical elements in ores, the study of variability of the material composition and stereometric features of ores in the geological space is extremely important to solve the problems of rational use of ore deposits and the prediction of environmental consequences of their development. When assessing the environmental impact of the deposits involved in the exploration and exploitation, both the regularities of distribution of toxic elements and minerals in the volumes of ore bodies and fields, and landscape-geochemical conditions determining the factors of migration and accumulation of these components after their extraction on the earth surface should be taken into account. For geological-economic and environmental forecasting it is necessary to accumulate materials on the distribution of impurity elements, sometimes not playing a role in assessing the industrial importance of deposits, but leading to the emergence of various man-made geochemical anomalies in areas of exploration and mining operations, as well as the formation of man-made deposits in places of waste storage of concentration plants and metallurgical plants.
Samarium-neodymium isotopic characteristics in minerals of gold-tungsten deposits of Olympiada, Olenye and greisen manifestation of tungsten Vysokoye-2 were studied. Isochron ages for mineralization of pre-mining quartz-wolframite-shelite, ore gold-shelite-sulfide, and post-mining fluorite-carbonate stages are 921.2 ± 7.5, 919 ± 93, and 915 ± 47 Ma, respectively. The e Nd (T) values in the minerals range from -1.3 in wolframite to -9.3 in scheelite 2 associated with gold, indicating their crustal nature. Model dating of T ( DM 2- st ) for minerals of pre-mining (1636-2053 Ma) and post-mining (1762-1806 Ma) stages correlates with the time of formation of granitogneiss domes in the region. The dating of T(VM 2- st ) for scheelite 2 (2250-2304 Ma) corresponds to the time of formation of tholeiite-basalt volcanics of the Indiglin complex, which can be considered as the primary source of gold. Gold mineralization in the interval 921-915 Ma resulted from remobilization of gold from the black shale strata and its redeposition during thermal-fluid impact during intrusion of granitoids of the Tartar-Ayakhta Complex at the 930-950 Ma.
Multistage Au-Sb-W mineralization of the Verkhne-Yenashinskoye ore cluster is found in deposits and ore occurrences of endocontact granitoids (Vysokoye-2) near-exocontact (Olenye, Innokentievskoye) and far-exocontact (Olimpiada). There are five stages of ore mineralization (from early to late): quartz-wolframite-sulfide with quartz-wolframite and scheelite-sulfide mineral associations, gold-sulfide with scheelite-pyrrhotite and gold-arsenopyrite associations, polymetallic with sphalerite-chalcopyrite-pyrrhotite and ulmanite-pyrite associations, gold-sulfoantimonite with pyrrhotite-bertierite, gold-goodmundite-anshmo-nite and association of native elements; postdepositional carbonate, The arsenopyrite geothermometer determined the possible temperatures of arsenopyrite formation of different generations HV: 430±50, 335±60, 395+90, and less than 280°C. Mineralogical zoning of the knot, which consists in the change of high-temperature mineralization of early stages to low-temperature late stages as the distance from the granitoid intrusion is revealed. The presence of cobalt, nickel and mercury minerals in the polymetallic stage at the Olympiad deposit is due to its confinement to the junction of ore-controlling faults with the zone of the deep regional Tatarsky fault.
Olimpiada, Oleniye and other gold-sulfide deposits are localized in terrigenous-carbonate rocks. The main ore minerals are arsenopyrite, pyrrhotite, antimonite, scheelite; rare minerals are wolframite, pyrite, bertierite, sphalerite, galena, chalcopyrite, tetrahedrite, jemsonite, gudmundite, coloradoite, zumoite, aurostibite, native gold and antimony. Gold in ores is present in three different forms: native (assay 910-997) in association with scheelite, pyrrhotite and arsenopyrite; chemically bound in arsenopyrite structure (up to 0.6 % by mass); aurostibite AiBg, coexisting with antimonite and Sb-sulfosoles. Ore elements are represented by the association (Au-As)i(Sb-Pb-Ag) at Olympiada and (Au-Ag-W)±Sb at Olenyi; their differences are due to variations in the mineral composition of ores: early gold-arsenopyrite and late silver-bearing sulfoantimonite with aurostibite (Olympiada); early gold-shelite-pyrrotite and late aurostibite-antimonite (Olenyi). The Au-Sb-W mineralization formed during the early rare-metal (quartz-wolframite, quartz-shelite-sulfide association) and later gold ore (gold-shelite-pyrrhotite, gold-arsenopyrite, polymetallic, gold-bertierite-antimonite, carbonate-fluorite-pyrite associations) phases.
