MINERALOGICAL AND GEOCHEMICAL FEATURES OF SATPAEV Ti-Zr PLACER DEPOSIT, EAST KAZAKHSTAN

Abstract

The data of mineralogical and geochemical studies of Ti-Zr mineral sands and heavy fraction of the mineral concentrate of Placer No. 1 of the Satpaev deposit (East Kazakhstan) are obtained. The mineralogical composition of the mineral sands: quartz, albite, ilmenite, and feldspar; micro-sized crystals of barite, zircon, monazite, a mineral of pyrochlore composition, were identified by electron microprobe. Crystal morphology of ore minerals: ilmenite and zircon and chemical composition of ilmenite were determined. The development of leucoxenization in microcracks and edges of ilmenite crystals have also been revealed. Geochemical features of productive horizons include the apparent enrichment of light rare-earth elements (LREE) in comparison with heavy rare-earth elements (HREE), and pronounced negative Eu anomaly that indicate high degree of fractionation of source rocks. Granitoids of the Preobrazhensk intrusion are the likely source of the Satpaev placer deposit. Results of petrological and geochemical research indicate that localization of ore minerals took place during chemical weathering, which enabled release of ore minerals of titanium and zirconium with their further redeposition in local continental coastal settings in warm and humid climate.