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Information × Registration Number 0220U000225, 0118U002184 , R & D reports Title Development of criteria of REE-potential in Precabrian rocks of the Ukrainian Shield popup.stage_title Head Kryvdik Stepan Grigorovich, Registration Date 23-01-2020 Organization nstitute of Geochemistry, Mineralogy and Ore Formation popup.description2 All known deposits and ores of rare earth elements in the Ukraine are genetically related to the three major complexes of igneous rocks, which are concentrated mainly in the Azov part of the USh: 1) alkaline-carbonatite and their metasomatites; 2) gabbro-syenitic massifs whose evolution is completed by nepheline or agpaitic syenites; 3) alkali-feldspar or rare-metal syenites were formed during of final stages of anorthosite-rapakivi granite plutons formation or their syenitic analogues. The prospect of alkaline acidic rocks as to the possibility of detecting REE ores is still uncertain, due to low distribution and small intrusive rocks volume. In peraluminous (rare metal) granites of the USh, REE mineralization is quit poor and does not have economic significance. Geochemical peculiarities of alkaline-ultrabasic complexes of the USh indicates that their massifs in the western and north-western parts are not very promising for the detection of significant occurrences of REE. This is related with their formation in collision tectonic settings, small scales, in the northern part - low differentiation too. In the alkaline-ultrabasic complexes of the Azov region the ore-bearing rocks are presented by Proterozoic carbonatites calcite-dolomite composition, which are formed in the later stages of the massifs formation. In connection with the latter, enriched with REE-apatite silicate-carbonate rocks and small in size but rich in REE-mineralization carbonatites bodies were crystallized from enriched with CO2, F, alkalis and REE residual fluids (Petrivsko-Gnutyvske deposit) might also be very interesting. With crystallization of residual alkaline fluids connected with carbonatitic intrusions are related unique REE mineralization of the Anadol-type ores. Within anorthosite-rapakivi granite plutons, as well as their syenitic analogues, complex REE-Zr mineralization of Azov- and Yastrubetse-type could be expected in connection with highly differentiated layered intrusions of alkaline-feldspar syenites. In many cases, in crystalline rocks of the USh deposits and occurrences of REE are associated with small bodies of specific rocks that are unusual or not gangue in other parts of the world, what requires appropriate adjustments in prospecting and exploration approaches and techniques. Product Description popup.authors Дубина Олександр Володимирович Кривдік Степан Григорович Степанюк Леонід Михайлович Шеремет Євгеній Михайлович popup.nrat_date 2020-04-02 Close