N. I. Gusev, V. E. Rudenko, N. G. Berezhnaya, S. G. Skublov, A. N. Larionov
Isotope-geochemical features and age (SHRIMP II) of metamorphic and igneous rocks in the Kotuykan-Monkholinskaya zone of the Anabar Shield
The paper presents data on bulk rock composition, U-Pb zircon age determinations (SHRIMP II), the isotopic composition of Nd and Sr for metamorphic and igneous rocks of the Kotuykan-Monholinskaya tectonic zone. The trace elements compositions of zircons from Proterozoic quartz-amphibole schists (2024 ± 20 Ma), anorthosites (1959 ± 9 – 1862 ± 25 Ma), pyroxenites (2079 ± 77 Ma) are studied. The granitoids presents by Late Archean sanukitoids (2702 ± 9 Ma), Proterozoic granites and blastocataclasites (1963 ± 16 – 1818 ± 27 Ma). The Nd model age for sanukitoids and anorthosite of 3.2–3.0 Ga, for Proterozoic quartz-amphibole schists and granitoids of 2.74–2.65 Ga.
Key words: Anabar Shield, granite-gneiss, anorthosites, pyroxenites, sanukitoids, zircon composition, U-Pb age.