Abstract
Porphyry copper deposits are one of the main sources of copper in the world and are usually associated with intrusive complexes of calc-alkaline composition formed in subduction-related geodynamic settings. Eastern Kazakhstan is characterized by the presence of a number of large porphyry copper-molybdenum deposits, but the metallogenic potential of many intrusive complexes in the region remains insufficiently studied. This paper presents new geological, mineralogical, and geochemical data on the Bala-Urpek deposit, located within the Sarykol intrusive complex (Eastern Kazakhstan), aimed at identifying diagnostic criteria for porphyry copper mineralization. The present study is based on field geological observations, petrographic analysis, and whole-rock geochemical data obtained by XRF and ICP-MS. Intrusive ore-bearing rocks are mainly represented by granitoids of the calc-alkaline series with I-type geochemical characteristics. Mineralogical studies have revealed veinlet-disseminated sulphide mineralisation, represented mainly by chalcopyrite and pyrite, as well as the development of hydrothermal alteration associations typical of porphyry systems. The geochemical characteristics of the rocks, including enrichment with large-ion lithophile elements and depletion with high-charge elements, indicate the subduction nature of magmatism. The combination of the data obtained allows us to identify geological, mineralogical and geochemical criteria characteristic of copper-porphyry systems and indicates the potential of the Bala-Urpek deposit area and the associated apophyses of the Sarykol complex for further exploration and prospecting.