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Information × Registration Number 0208U004503, 0106U006615 , R & D reports Title Geochemical, genetical peculiarities and problems of ore-bearing ability of alkaline complexes in different structures of Eurasia (platforms, shields and folded belts) popup.stage_title Head Kryvdik Stepan Grygorovych, Registration Date 24-11-2008 Organization nstitute of Geochemistry, Mineralogy and Ore Formation popup.description2 It is established the geochemical heterogeneity of Azov and Western parts of the Ukrainian Shield (US) is caused by different geodynamic conditions of their formation. The massifs of alkaline rocks of the Azov part of the US was formed in rift conditions, whereas the massif of Western part - in collision conditions. Unusual mineralogical peculiarities of alkaline rocks can be explain with the greater (up to 20 km) or substantial erosion cut of their. The level of erosion cut is reflected in the geochemical peculiarities of alkaline rocks. Hypabyssal intrusions (Gorodnytca, Glumcha, Pokoshev dikes) are significantly depleted in Zr, TR and Nb compared to deep-eroded Proskurovka and Antonovka massifs. Similar peculiarities is observed in the line-elongated Chernigovka carbonatite massif. It is established different trends of differentiation and features of trace-elements distribution in alkaline rocks of alkali-ultrabasic and gabbro-syenite complexes, that is explained by different mechanisms of melts fractionating. The principal mechanism of gabbro-syenite multiphase massifs is crystallization differentiation (with feldspar fractionating), whereas for alkali-ultrabasic massifs the main process is liquation of the parent melt in silicate and carbonate components. It is possible of liquation of melanocratic melts with phonolite separation. During the investigation of agpaitic phonolites from the Oktiaberskiy massif had been discove and analyze rare minerals: Na-katapliite, serandite, REE-eudialite, hendricksite, cryolite, melacerite, enriched in REE and Na apatite. Product Description popup.authors popup.nrat_date 2020-04-02 Close