Skarnization and Fe Mineralization at the Western Orebody in the Manjang Deposit, Goesan

Abstract

The Manjang deposit is emplaced in Hwajeonri formation comprising limestone that is interbeded with slate and phyllite in the central Okcheon Group. It consists of the Main and the Central orebody of Cu-bearing hydrothermal vein deposit and the Western orebody of iron skarn deposit. Based on coexisting mineral assemblage the skarnization can be divided into prograde skarnization (stage I : clinopyroxene ± magnetite ± quartz, stage II : garnet + clinopyroxene ± magnetite ± quartz) and retrograde hydrothermal alteration (stage III: magnetite + amphibole + quartz ± garnet ± clinopyroxene± chlorite ± epidote ± fluorite ± calcite, stage IV: fluorite ± pyrrhotite ± chalcopyrite ± amphibole ± quartz ± calcite). Diopside is abundant in stage I, and hedenbergite was produced in stage II and III. Garnet compositions change from grandite to andradite, which suggests a redox transition from relatively reduced to oxidized condition during the skarn formation. Magnetite in *Corresponding author: +82-41-850-8509, E-mail: shin@kongju.ac.kr