Composition of zircon in the Elinovskii massif (Gorny Altai)

Gusev A. I.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2017. V. 146. N 4. P. 54-65

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Language: Russian

Abstract

The paper displays new data on U-Pb zircon age of riebeckite granite of the Elinovskii massif in the Gorny Altai and presents comparative characteristics of morphology and chemical composition of magmatic and hydrothermal zircon. The presence of well-developed crystal faces {100} and the absence of crystal faces of prysm {110} in magmatic zircon point to the high temperature of melt. Hydrothermal zircon is a bipyramid in shape with well-developed crystal faces {111}, that being it is like synthetic crystals. Magmatic zircon is characterized by high concentrations of Hf, Y, Sc, and REE. It has intensive cerium anomaly and negative europium one. Unlike magmatic zircon, hydrothermal zircon shows rather low concentrations of Sc, Y, and relatively high contents of LREE, Nb, Ta, Ti. Also, it is enriched in the total sum of REE. The M-type tetrad effect in REE is recognized in both types of zircon.

Key words: riebeckite granite, leucogranite, U-Pb age, zircon, rare earth elements, tetrad effect in REE, Gorny Altai.