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The Baghu gold deposit, hosted by a granitoid stock as well as volcanic rocks, is located in Northern Iran. The igneous rocks consist of granodiorite and granite as well as volcanic rocks, such as basaltic andesite and andesite, which are cut by dioritic dykes. The igneous rocks have metaluminous, high K calc‐alkaline, and island‐arc signatures, characterized by enrichment in large‐ion lithophile elements (LILEs) and depletion in high‐field‐strength elements (HFSEs). Zircon separates yield U–Pb ages of 47, 43, and 38 Ma for the volcanics, granitoid rocks, and dyke, respectively, indicating that the magmatism associated with gold–copper mineralization occurred during the Eocene. The low Ba/Th, Th/Nb, Ba/La, and Th/Yb ratios in igneous rocks indicate that their mantle source was not likely modified by subduction activity. A comparison of La/Sm against La (ppm), similar Th/Nb and Th/Yb, and average (La/Yb)n ratios to the crust and lower continental crust (LCC) suggests that the magmatism in the Baghu was likely associated with partial melting of juvenile lower crust, induced by north‐westward subduction of the Neo‐Tethys oceanic lithosphere in an extensional setting. [ABSTRACT FROM AUTHOR]

The Kharapeh gold deposit is located along the northwestern margin of the Sanandaj-Sirjan Zone (SSZ) in the West Azerbaijan province, Iran. It is an epizonal orogenic gold deposit formed within the deformed zone between central Iran and the Arabian plate during the Cretaceous-Tertiary Zagros orogeny. The deposit area is underlain by Cretaceous schist and marble, as well as altered andesite and dacite dikes. Structural analysis indicates that the rocks underwent tight to isoclinal recumbent folding and were subsequently co-axially refolded to upright open folds during a second deformation. Late- to post-tectonic Cenozoic granites and granodiorites occur northeast of the deposit area. Mineralization mainly is recognized within NW-trending extensional structures as veins and breccia zones. Normal faults, intermediate dikes, and quartz veins, oriented subparallel to the axial surface of the Kharapeh antiform, indicate synchronous extension perpendicular to the fold axis during the second folding event. The gold-bearing quartz veins are >1 km in length and average about 6 m in width; breccia zones are 10-50 m in length and ≤1 m in width. Hydrothermal alteration mainly consists of silicification, sulfidation, chloritization, sericitization, and carbonatization. Paragenetic relationships indicate three distinct stages-replacement and silicification, brecciation and fracture filling, and cataclastic brecciation-with the latter two being gold-rich. Fluid inclusion data suggest mineral deposition at temperatures of at least 220-255°C and depths of at least 1.4-1.8 km, from a HO-CO±CH fluid of relatively high salinity (12-14 wt.% NaCl equiv.), which may reflect metamorphism of passive margin carbonate sequences. Ore fluid δO values between about 7‰ and 9‰ suggest no significant meteoric water input, despite gold deposition in a relatively shallow epizonal environment. Similarities to other deposits in the SSZ suggest that the deposit formed as part of a diachronous gold event during the middle to late Tertiary throughout the SSZ and during the final stages of the Zagros orogeny. The proximity of Kharapeh to the main tectonic suture of the orogen, well-developed regional fold systems with superimposed complex fracture geometries, and recognition of nearby volcanogenic massive sulfide systems that suggest a region characterized by sulfur- and metal-rich crustal rocks, collectively indicate an area of the SSZ with high favorability for undiscovered gold resources. [ABSTRACT FROM AUTHOR]