RARE-METAL METASOMATITES IN KEIVSKO-KOLMOZERSKAYA ZONE (KOLA PENINSULA)

摘要

The rare-metal metasomatites in Kola region are divided in two type: IN differing, first of all, by the age of their formation: AR_2 and PR_1, respectively. Both types have a similar process of the initial rocks alteration, but different geochemical specialization. The Later Archean metasomatites are specialized on Li, Rb, Cs, but the Earlier Proterozoic ones have specification for Zr. Y and REE. The higher F content is responsible for movement and concentration of rare elements; from the other side, the consequent change of pH in fluids should be the main reason of their differentiation over zones of metasomatism.