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Information × Registration Number 0217U001120, 0111U005653 , R & D reports Title Petrology and metallogenity of alkaline rocks of the Azov area popup.stage_title Head Kryvdik Stepan Grigorovich, Registration Date 24-01-2017 Organization nstitute of Geochemistry, Mineralogy and Ore Formation popup.description2 In alkaline and subalkaline massifs of gabbro-syenitic massifs of the Azov area denote clearly the enrichment in iron (Fenner's) trend. It manifests by growing iron content and alkalinity in rocks and femic minerals from early to late rocks. The latest (residual) syenites are enriched (to ore concentrations) in incompatible elements (REE, Y, Nb, Ta, Zr, Hf) but are depleted in Sr and Ba. Theses rocks have deep negative Eu-anomalies. Such features of evolution of gabbro-syenitic complexes are confirmed by mechanism of crystallization differentiation with strong feldspar fractionation. In alkaline-ultramafic complexes, unlike to gabbro-syenitic ones, this trend is absent or slightly expressed. In these complexes incoherent and rare element distribution is more complicated. They concentrate mainly in carbonatites or apofenitic albitites. The negative Eu-anomalies in REE pattens is slightly manifested or absent for all types of these rocks. The distribution of trace elements in alkali silicate rocks and carbonatites from alkaline-ultramafic complexes is explained more satisfactory by liquation of primary melts into silicate (nephelinite, phonolite) and carbonatite components. Different ways of crystallization and composition of primary melts are caused various ore mineralization. In gabbro-syenitic complexes rich rare-metal mineralization is formed only in the latest and residual syenitic rocks while high content of apatite and ilmenite are connected with early gabbroids and pyroxenites. At the same time the alkaline ultramafic complex rare-metal mineralization (together with apatites) is concentrated mainly in carbonatites. Product Description popup.authors Гаценко Вра Олексіївна Дубина Олександр Володимирович Кривдік Степан Григорович Луньов Євгеній Сергійович Мінеєва Віра Миколаївна Моргун Вячеслав Григорович Томурко Людмила Леонідівна Шнюкова Катерина Євгенівна popup.nrat_date 2020-04-02 Close