Oxidation of the Kupferschiefer in the Lubin-Sieroszowice deposit, SW Poland: Evidence from petrographic and geochemical studies

摘要

Studies of core and mine samples from the western part of the Lubin-Sieroszowice deposit (Polkowice area) imply an extensive secondary oxidation of the lower part of the Kupferschiefer sequence, leading to the formation of the Rote Faeule facies. The mineralization process results in a clearly defined threefold division, consisting of oxidised rocks at the base, a transitional zone in the central part and reduced rocks in the top of the Kupferschiefer sections studied. Relicts of organic matter, replacements of pyrite and copper sulfides by iron oxides, high concentrations of Au, Pt and Pd, and an increase of V/Cr ratio characterize the transition zone. The alteration of organic matter and of the C, O and S isotope ratios reflect interactions of ascending fluids with the host rocks.