SOURCES AND MECHANISMS OF FORMATION OF ALKALINE RARE-METAL GRANITES AT THE ZASHIKHINSKY MASSIF BASED ON GEOCHEMICAL AND Nd ISOTOPE DATA

The intraplate alkaline-granite magmatism essentially contributes to formation of rare-metal strategic raw materials. In the Major Sayan Fault East Mountains, rocks Zashikhinsky (Pz 3 ) massif were studied through isotope-geochemical analysis identify probable sources magma and mechanisms their evolution resulting in ore accumulations, up Nb-Ta deposits. Nd isotopic characteristics its alkaline granites obtained for first time. Together with results mineralogical geochemical studies, they applied modeling formation, which crystallization differentiation granite melts proceeds simultaneously assimilation enclosing granite-metamorphic formations.