Geodynamics and Metallogeny of Copper in the Middle Zone of Central Kazakhstan and its Prospects

Abstract

In the middle part of Central Kazakhstan there are linear copper-bearing riftogenic-orogenic zones of sublatitudinal strike (Spassk and Uspensk zones) with numerous sulfide and porphyritic deeply eroded deposits and ore occurrences of copper not currently presenting commercial interest due to insignificant reserves and Zhezkazgan basin conjugated with them in which first-rate deposits of cupriferous sandstones are located. Formation of sulfide deposits occurred in the process of riftogenesis, and porphyritic deposits were formed in orogeny. Copper was carried away by river waters together with broken rocks, minerals and organic matters from the mentioned zones with humid climate into arid littoral-deltoid areas of the Zhezkazgan sea basin in the Carboniferous-Permian, where water soluble copper compounds sedimented under the influence of hydrogen sulphide of biogenic sulfate-reduction. Gradual upthrusting of the north side of the basin shifted the riverbed in the undercurrent many times. This resulted in forming of deposits of different ages: from the Middle (The North group) and Middle-Upper Carboniferous (Zhezkazgan) to the Upper Permian (Taskora). It is possible that between the latter ones there are some large deposits localized in lenses of alluvial deposits controlled by paleofaults situated in multiple distances. To discover them a complex of geological and geophysical prospecting methods is proposed.