Listwaenitization and Enrichment of Precious Metals in the Hydrothermal Mineralization Zones of Serpentinites in Sugecer-Van (Eastern Anatolia, Turkey)

Abstract

An ophiolitic complex containing hydrothermally altered serpentinized ultramafic rocks was studied in an area on the eastern side of Lake Van near the village of Sugecer, Eastern Anatolia. Field observations and petrographic and geochemical analyses clearly showed that the serpentinites were altered to listwaenites via silicification and carbonatization. The listwaenites were classified as type-I and type-II listwaenites based on their mineral composition. The type-I listwaenites contained carbonate minerals, rare serpentine minerals, chromite and mariposite, whereas the type-II listwaenites contained mainly silicate minerals. The listwaenites were enriched in Au, As, Cu, Ni and Co relative to the serpentinites. The listwaenites also showed chondrite-normalized enrichment in light rare earth elements and depletion in heavy rare earth elements. The effects of tectonism were widely observed in the study area. Mineral enrichment in the Sugecer region was shown to be associated with the transport of minerals by hydrothermal fluids under the influence of tectonism.