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Information × Registration Number 0216U002198, 0111U001015 , R & D reports Title Genesis of uranium deposits of central part of the Ukrainian Schield popup.stage_title Head Syomka V.O., Registration Date 02-02-2016 Organization nstitute of Geochemistry, Mineralogy and Ore Formation popup.description2 Object of the research: ore occurrences and deposits of potassium- and sodium-uranium rock association in Precambrian complexes of central part of the Ukrainian Shield (USh). Aim of the research: geochemistry, mineralogy and age of uranium ores of Precambrian complexes in the USh. Research methods: ore petrography, petrography, energy dispersive spectrometry, scanning electronic microscopy, isotope mass-spectrometry, geochemical. New results of the research of occurrences and deposits of sodium-uranium formation of the USh by means of mineralogical, petrological, isotopic techniques are presented. It is shown that Precambrian and Achaean organogenic sedimentary rocks enriched in uranium, thorium, rare-earth elements, molybdenum and bismuth were as primary source of rare-earth-uranium-thorium mineralization. The age of ore-bearing aplite-pegmatoid granites and related rare-earth-uranium-thorium metasomatites of potassium-uranium rock association is determined. It varies from 1981 to 2047 Ma; monazite dating. Mineral composition of main hypogenic and hypergenic minerals of uranium such as uraninite, pitchblende, coffinite, thorite, thorianite, schoepite, and thorium such as monazite, rhabdofan, thorite, thorianite, thorogummite, zircon. Physical and chemical conditions of formation of uranium-bearing metasomatites have been defined. Complex character of ore potential of sodium-uranium rock association is illustrated: uranium, vanadium, scandium, etc. Apogranitic albitites have been formed in wide temperature range which corresponds to middle and high-temperature metasomatic facies. Medium-temperature condition is characteristic for epidote-chlorite metssomatic column, up to 350 ?C, and riebeckite-aegirine one, from 350 C to 450 C. Garnet-diopside albitite is assigned to high-temperature association (over 450°С). Mineral paragenesises of carbonate-hematite-phlogopite (chlorite) association of post-albite stage are classified to low-temperature association, up to 300°C. Uranium minerals of sodium uranium-bearing metasomatites were studied. Hypogenic ones as uraninite, brannerite, davidite, and hypergenic ones as pitchblende and hydroxides of uranium were defined among them. New minerals in uranium-bearing albitites as native lead, copper, silver, senaite, Ce-uekfildit, strontium barite have been detected first time. The age of formation of uraninites of the Vatutinskoe deposit, 1724-1752 Ma, is defined; it is close to the age of rapakivi-anortosites of the Korsun-Novomirgorod pluton. Main points of view on genesis of uranium-bearing sodium metasomatites are presented. Novelty: first time material composition and age of the deposits and occurrences of potassium- and sodium-uranium rock association have been thoroughly studied; complex character of ore potential has been defined. Application area: results of the research were used by exploration institutions as "Kirovgeologia" state enterprise during prospecting works on uranium in different megablocks of the USh. Product Description popup.authors Бондаренко Сергій Миколайович Карли Захар Вадимович Мельниченко Борис Федорович Михальченко Іван Іванович Синицин Василь Олександрович Степанюк Леонід Михайлович Сьомка Володимир Олексійович Шумлянський Леонід Владиславович popup.nrat_date 2020-04-02 Close