Е. N. LEPEKHINA, А. V. ANTONOV, B. V. BELYATSKY, N. V. RODIONOV,
N. G. BEREZHNAYA, S. S. SHEVCHENKO, S. A. SERGEEV (VSEGEI)

Some features of U-Pb SHRIMP dating of pyrochlore from alkaline-ultramafic polyphase Kovdor massif (North Karelia): isotope-geochemical characteristics of the evolution of pyrochlore-group mineral composition

The results of isotope dating of alkaline-ultramafic polyphase massifs and carbonatites, and related rare-metal mineralization by pyrochlore U-Pb SIMS SHRIMP II method developing within CIR VSEGEI are presented. Some challenges of this dating method and interpretation approaches are discussed on the example of Paleozoic alkaline-ultramafic Kovdor massif (North Karelia) pyrochlore collections.

Keywords: pyrochlore, U-Pb local dating, SHRIMP II, Kovdor massif, rare-metal mineralization, isotope-geochemical characteristics, alkaline-ulramafic massif, carbonatites