Fluorine-Beryllium Deposits of the Vitim Highland,Western Transbaikal Region:Mineral Types,Localization Conditions,Magmatism,and Age

摘要

The fluorine-beryllium deposits of the Vitim Highland are represented by two mineral types:feldspar-fluorite-phenakite-bertrandite and thorite-fluorite-phenakite.Their localization is controlled by fault zones of various orders,folds,and stocks and dikes of the Early Mesozoic subalkali quartz syenite and syenite porphyry.The ore is represented by mineralized crush zones and metasomatic veins hosted in intercalated carbonate and aluminosilicate rocks.The deposits were formed under hydrothermal conditions at 360-90 deg C;their age is estimated at (243+-3)-(260+-2) Ma.