The geology of the Bozymchak Cu-Au skarn deposit,Tien Shan belt,Central Asia: Emphasis on the geochemical characteristics of the granitoids

Abstract

The Bozymchak Cu-Au skarn deposit is located in the Chatkal – Kurama region, approximately 130 km east from the Almalyk Cu-Au porphyry mine camp. The current paper provides the results from geochemical study and shows that geochemical characteristics of the Bozymchak area granitoids, including the rare-earth elements, are essentially similar to high-K calc-alkaline series magmatism of the Almalyk area. Systematic sampling of the Bozymchak granitoids has revealed the zoned distribution of several elements relative to the Cu-Au skarn. Most markedly, this is expressed by P₂O₅, MgO, Fe₂O₃ and V, whose contents decrease in the granitoids located closest to the skarns. The zoned distribution of base metals Cu, Zn, Pb, Mo, and also As, is less distinct, however, in general, their content decreases away from the skarns. This revealed geochemical zoning appears to represent a hydrothermal halo of Cu-Au bearing skarns and can potentially be used for guiding exploration in the region.