Manganese ores in black shales sequences in the Western Carpathians, Slovakia

摘要

Manganese carbonates in shale with increased content of organic matter were formed in anoxic environment during the Paleogene, Jurassic and Early Paleozoic. The Early Paleozoic carbonates of manganese underwent the Hercynian metamorphism together with silicate minerals and manganese silicates were formed. Manganese oxides and hydroxides were formed during supergene alteration of sedimentary-diagenetic and metamorphic manganese ore.