Geology, geochemistry and stable isotope thermometry in the Shovey gold- bearing polymetallic deposit, northwest of Baneh

Document Type : Original Article

10.22128/ijcm.2025.2985.0

Abstract

The Shovey Au-bearing polymetallic deposit is located in the northwestern part of the Sanandaj-Sirjan zone, 7 km northwest of Baneh. The exposed rock units in the study area are the Late Protozoic and Cretaceous volcano-sedimentary sequences consisting of schist, phyllite, metaandesite-basalt lavas, and crystalline limestones (marble). The orebodies are composed of galena, sphalerite, pyrite, tetrahydrite and gold. The maximum amounts of Au and Ag in the orebodies are 3 and 104 ppm, and the maximum amounts of Cu, Pb and Zn are 4.22, 0.34 and 0.57 %. in silicic-sulfide berecias and veins, within the limestone host rock. The native gold (5–35 µm) occurs along quartz, pyrite and sometimes tetrahydrite grain boundaries. The δ³â´S values ​​in galena and sphalerite minerals ranges from -10.4 to 1.4 ‰ and fall within the range of values observed for orogenic deposits. Calculated sulfur isotope temperatures for coexisting galena-sphalerite pairs range from 144 to 336°C, which is consistent with temperatures obtained from fluid inclusions studies. The δ¹â¸O values ​​of the ore-forming fluid ranges from 9.8 to 13.7‰. Studies on regional geology, mineralization, geochemistry and stable isotope characteristics of the Shovey deposit reveal greatest similarity to orogenic gold deposits.

 

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