Geochemical, mineralogical and sulfur isotopic evidence on the genesis of the Gadir Au-Ag-Cu-Pb-Zn deposit (NW Azerbaijan) in the Lesser Caucasus

Abstract

The Gadir Au-Ag-Cu-Pb-Zn deposit, located in the western part of Azerbaijan, was extensively occurred in quartz porphyry, and rarely in the contact of the hornfelsed andesite and quartz porphyry. The hydrothermal alterations associated with mineralization are quartz-adularia +/- sericite and propylitic alterations. The Gadir deposit is mainly composed of native gold, hessite, chalcopyrite, sphalerite, galena, pyrite, minor arsenopyrite, marcasite, digenite, barite, and adularia. The Gadir deposit is mainly composed of Au, Ag, Cu, Pb, and Zn which maximum quantities are 10.3 ppm, 1133 ppm, 23780 ppm, 59811 ppm, and 424770 ppm, respectively. The delta S-34(H2S) values (-2.2 to 4.4 parts per thousand) of sulfides (chalcopyrite, pyrite, and sphalerite) from the Gadir Au-Ag-Cu-Pb-Zn deposit indicate a magmatic origin for the ore-forming fluids. The geological, mineralogical, geochemical, and isotopic data for Gadir deposit suggest an epithermal deposit associated with the porphyry system.