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Information × Registration Number 0216U002200, 0113U003382 , R & D reports Title Mineraloge-geochemical regularity of U-TR-Th-ore localization in central and western parts of Ukrainiane Schield popup.stage_title Head Stepanyuk Leonid Michailovitsch, Registration Date 02-02-2016 Organization nstitute of Geochemistry, Mineralogy and Ore Formation popup.description2 Object of researches - ore manifestations and deposits of potassium-uranium formations in Precambrian complexes of the central and western part of Ukrainian Shield (USh). Aim of work - to develop mineralogo-geochemical and age criteria of searches for uranium- rare-earth - thorium deposits in Precambrian complexes of central and western part of USh. Methods of researches - geochronological (uranium-lead and rubidium-strontium methods), geochemical, mineralogical, petrographic, micro-X-ray-spectral, electronic microscopic and field works. New results of ore-mineralogical and geochronological studying of ore manifestations and deposits of potassium-uranium formation in central and western parts of USh are shown. Mineralogical composition of uranium - rare-earth - thorium mineralization represented by apatite, zircon, monazite, thorite, xenotime, rabdophanite, uraninite, nasturan, brannerites, coffinite, uranium black, lindokite, molybdenite, native bismuth and bismutite is studied in details. Paragenetic ore mineral associations from high through middle to low-temperature ones are distinguished. It is established, that primary source of rare-earth - uranium - thorium mineralization were sedimentary Proterozoic and Archean rocks enriched in uranium, thorium, rare earths, molybdenum and bismuth. Aplite-pegmatitic granites and associated silica-potassic metasomatites were formed at granitisation of these rocks. numerical values of primary ratios 87Sr/86Sr in plagioclases from ore-bearing aplite-pegmatitic granites varying in wide range from 0.70772 to 0.71308 festify for this fact. These numerical values of primary ratio 87Sr/86Sr are the same for plagioclases from silica-potassic metsomatites. The consecutive and one-act nature of ore mineralisation in potassium-uranium formation is also proved by mineralogo-petrographic researches. Ore mineralization in rocks pf potassium-uranium formation of USh was formed within following age intervals: Volyn megablock - 2080-2040 million years; Dniester-Bug megablock - 2060-1980 million years, Holovanivka sutural zone - 2040-2020 million years. As the result of carried researches following criteria of localisation of uranium - rare-earth - thorium mineralization in Precambrian complexes of central and western part УЩ are revealed. Among which are structural, magmatic, lithological, geochemical and mineralogical ones. Novelty - for the first time in the Ukrainian Shield composition and age of deposits and new ore manifestations pf potassium-uranium formation is investigated in details and criteria of their localisation in Precambrian complexes of central and western part of USh are established. Area of use - Results of SIW were used by industrial organisations KP "Kirovgeology" at carrying out geological searches for uranium in different megablocks of USh. Product Description popup.authors Бондаренко Сергій Миколайович Степанюк Леонід Михайлович Сьомка Володимир Олексійович popup.nrat_date 2020-04-02 Close