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Information × Registration Number 0217U001115, 0112U002428 , R & D reports Title Thorium mineralization in the Precambrian complexes of the Ukrainian Shield; mineralogy, geochemistry popup.stage_title Head Stepaniuk Leonid Mykhailovych, Registration Date 24-01-2017 Organization nstitute of Geochemistry, Mineralogy and Ore Formation popup.description2 New results of mineralogical, geochemical and geochronological study of ore occurrences and deposits of potassium-uranium rock association of the Ukrainian Shield (USh) are presented. Chemical composition of thorium minerals has been thoroughly studied, paragenetic ore mineral associations from high-, medium- to low-temperature ones have been defined. High contents of thorium exceeding abundances for rocks of USh have been established for aplitic-pegmatoid granites, significantly microclinic pegmatites, related silica-potassium magnesia-iron-potassium metasomatites. Among host rocks exceeded contents of Th are typical for graphite-bearing gneiss, aplite-pegmatoid granite, related to it pegmatite and ore-bearing metasomatite. Three last ones were formed from graphite-bearing gneiss during granitization. Major Th-minerals in ore-bearing metasomatites of silica-potassium rock association are monazite, thorite, uraninite (the Bezymennyi ore occurrence); monazite, uraninite (the Khmilnitskyi and Zavalie ore occurrence); monazite (the Haivoron ore occurrence and Ostapivske deposit); monazite, thorite, uraninite, coffinite (the Kalynivske deposit); monazite, pitchblend, brannerite (the Dibrovske deposit). Two stages of thorium minerals formation in the USh during Precambrian have been established: Paleoproterozoic, 2080-1960 Ma, and Mesoarchaean, 2933-2786 Ma. Last one is in Eastern part of the USh only. Product Description popup.authors Бондаренко Сергій Миколайович Донський Микола Олександрович Карли Захар Вадимович Степанюк Леонід Михайлович Сьомка Володимир Олексійович popup.nrat_date 2020-04-02 Close