Xenotime mineralization in various structural-substantial complexes of the Bashkir meganticlinorium (the South Urals)

Kovalev S. G., Kovalev S. S.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2022. V. 151. N 1. P. 74-91

https://doi.org/10.31857/S0869605522010075

Language: Russian

Abstract

The article presents data on abundence of xenotime mineralization and conditions of its formation in various structural-substantial complexes of the Bashkir meganticlinorium. Analysis of REE contents and nature of their distribution in rocks of various complexes indicate their significant mobility during metamorphism, due to both the composition and structure of the substrate, and the degree / parameters of its alteration. In the process of metamorphic alteration of terrigenous rocks, the detrital zircon acts as a selective concentrator of the heavy REE. The mechanism providing the presence of a significant amount of Y ions and geochemically close heavy REE in the crystal lattice of zircon is the isomorphic substitution of zirconium by yttrium. It has been revealed that the mechanisms of formation of the metamorphogenic xenotime mineralization are diverse, and they are controlled by the composition of substrate, the migration-sorption properties of REE and parameters of metamorphism.

Keywords: Bashkir meganticlinorium, xenotime mineralization, rare earth elements, metamorphism, metamorphogenic mineral formation