On genesis of“white granites” from the Kestersky harpolith (Arga-Ynnakh-Khaysky massif, East Yakutia)

Alekseev V. I., Marin Yu. B.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2020. V. 149. N 1. P. 47-63

https://doi.org/10.31857/S0869605520010049

Language: Russian

Abstract

The questions of genesis of “white granites” in the Kestersky harpolith of the Arga-Ynnakh- Khaysky massif are addressed. Morphology, attitude and features of intrusive contacts of the Kestersky harpolith prove its magmatic origin. Petrographic and petrochemical properties of “white granites” allow identifying them as postorogenic rare-metal high-phosphorus granites of the lithium-fluoric geochemical type. Magmatic genesis of “white granites” structure are confirmed by statistical methods. Species composition of accessory minerals, their typomorphic features, ontogenetic analysis of their internal structure and mutual relationship allow to conclude, that the main accessories of the granites – cassiterite, columbite, tantalite, wolframoixiolite, zircon, ferberite – were formed at the late-magmatic stage of evolution of the low-temperature rare-metal granite melt at subsolidus conditions. The Kestersky harpolith in the Arga-Ynnakh-Khaysky granite massif, and the same-named tin-rare-metal deposit genetically connected with it, are a part of the Far East superprovince of rare-metal granites.

Keywords: rare-metal high-phosphorus lithium-fluoric granite, accessory minerals, cassiterite, columbite-tantalite, Kestersky harpolith, Yakutia