Platinum-group element distribution in chromite ores from ophiolite complexes, western Turkey

Abstract

Selected chromite mines in western Turkey (Fig. 1) were the focus for a study of platinum-group element (PGE) and Au concentrations in chromite ores and host rocks. Forty-six underground chromite mines were sampled in ten districts. The chromite is hosted in peridotite, dunite, serpentinized harzburgite and Iherzolite rocks of late Jurassic to late Cretaceous age. A total of 113 ore and rock samples were collected and examined. High PGE concentrations are a feature of chromite-rich rocks worldwide in ultramafic complexes of Alpine type.(1,6,8,23,29) Knowledge of the geology and geochemistry of these deposits is, therefore, critical to understanding of the mechanism of PGE mineralization and its genesis. The study area contains numerous chromite deposits in a complex, ENE-trending suture zone between the Izmir-Ankara ophiolite zone in the north and the Taurides platform in the south. More than 200 chromite occurrences, prospects and mines are scattered throughout the peridotites, dunites and serpentinized Iherzholite-harzburgites(10).