MAIN TYPES OF COPPER DEPOSITS IN THE REPUBLIC OF KAZAKHSTAN

Copper mineralisation in Kazakhstan is represented by all of the major mineable and genetic types of copper deposits, including Cu-bearing sandstones, Cu-Mo porphyries, Cu-Pb-Zn massive sulfides, Cu skarns and Fe-Cu skarns. Kazakhstan is also prospective for unconventional types of copper deposits, such as magmatic Ñu-Ni-Pt, native Cu, Cu-Au-U veins, Cu pyrrhotite and "manto" type. Within the Shu-Sarysu depression of southern Kazakhstan, deposits of cupriferous sandstones of the Zhezkazgan type (i.e. Zhezkazgan, Zhilandy group, Zhaman-Aybat) are strictly confined to Permian–Carboniferous red sediments. Porphyry copper deposits are associated with intrusive complexes of three volcano-plutonic belts of different ages. Low-grade Cu-Mo ores typical of porphyry deposits related to granodiorite intrusions formed in late Palaeozoic orogenic belts. Higher-grade Cu-Mo-Au ores (Cu 1.5%) formed in Devonian (orogenic) and Caledonian (island arc) volcano-plutonic belts. These higher-grade deposits are typical of porphyry systems related to monzonitic intrusions and contain telescoping zones of supergene secondary enrichment. Cu-Pb-Zn deposits of massive sulfides were explored within volcanogenic complexes of the Rudny Altay, Maykain-Shiderty-Chingiz and South Uralian metallogenic zones. Explored Cu skarn deposits (Sayak group, Eshkeulmes) and Fe-Cu skarn deposits (Irisu, Kacharskoe) are of medium size; their contribution to total copper reserves (1.5%) and production (nearly 3%) in Kazakhstan is insignificant. The potential for unconventional types of copper ores can be assessed preliminarily and their commercial significance should be compared with similar deposit models on a global scale.