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The Hamzeh–Gharanin gold deposit (HGD) is located in the Qolqoleh–Kasnazan shear zone in the northwest of Sanandaj–Sirjan Zone (SSZ) and 40 km SW of Saqez. The main rock units are an assemblage of the Precambrian metasedimentary (pelitic) rocks and the Cretaceous phyllite associated with marble interlayers. The post–Cretaceous intrusive granitoids with NW–SE trends intruded within these two units. Mineralization occurs mainly within the NE–SW extensional veines and veinlets in proto–mylonitic, mylonitic and ultra–mylonitic rocks. Hydrothermal alterations consist of sericitization, carbonatization, silicification and chloritization. The main ore minerals include pyrite, chalcopyrite, arsenopyrite, pyrrhotite, sphalerite, galena, gold, magnetite and hematite. The fluid inclusions study from quartz minerals associated with the mineralization shows four different phases: single vapor phase (V; type I), single liquid phase (L; type II), liquid–vapor biphasic (LV; type III) and three phases (LLV; type IV). Microthermometric studies were performed on types III and IV of fluid inclusions. Homogenization temperatures (Th) for Types III and IV inclusions vary between 138 and 310 °C (mean 230 °C) and 250–335 °C (mean 300 °C) and their salinity varies between 0.52 and 13.87 and 4.79 to 9.58 (wt% NaCl), respectively. Moreover, the density of Types III and IV inclusions vary from 0.71 to 0.927 g/cm3 and 0.700–0.870 g/cm3, respectively. The oxygen (in quartz: 4.58–7.80 ‰; mean 5.82 ‰) and δ34S (in pyrite: 5.54–6.28 ‰; mean 5.91‰) isotope compositions of the mineralizing fluids indicate an insignificant meteoric water input during hydrothermal evolution and a magmatic origin of sulfur in the deposit which is broadly similar to those of orogenic gold deposits worldwide. [Display omitted] • This study presents the metallogenic processes and ore-forming fluids evolution in the Hamzeh–Gharanin Au deposit. • The deposit was formed during the continental collision in the shear zone. • The main characteristics of geology and mineralization are similar to orogenic gold deposits. [ABSTRACT FROM AUTHOR]

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 Malayer-Esfahan Metallogenic belt (MEMB), in the southwestern Iran, contains numerous different types of the sediment-hosted Zn-Pb (±Ba±Ag), volcanic-sediment hosted Zn-Pb ± Ba, sideritic Fe-Mn-Pb (±Ba±Cu), and barite mineralizations. These deposits are hosted mostly in Jurassic shales and sandstones and in Early to Late Cretaceous carbonates and siltstones with minor volcanic rocks. In contrast to the orogenic-related Mississippi Valley type (MVT) deposits, the MEMB deposits formed in an extensional back-arc environment and are characterized by their stratabound and stratiform orebodies. In these deposits, silicification and dolomitization (± sericitization) are the main wall-rock alteration styles. The presence of primary laminated sulfides, fine-grained disseminated sphalerite and galena in association with framboidal pyrite, sedimentary structures in sulfide laminae and bands, and the association of some tuffaceous and volcanic rocks with sulfide mineralizations, along with replacement ore textures in the MEMB deposits are not compatible with orogenic-related MVT model for these mineralizations. These characteristics in the Cretaceous MEMB deposits are more compatible with a sub-marine hydrothermal system with sub-seafloor replacement mineralization (e.g., Irish type). Some deposits also share characteristics between Irish type and volcanogenic massive sulfide (VMS) deposits, called VSHMS in this paper. The main argument against the MVT model of Karimpour and Sadeghi (2018) is that this model is not acceptable for the MEMB deposits and could not explain metallogenic aspects of the Zn-Pb (±Ba±Ag) and other mineralizations in this belt. Unlabelled Image [ABSTRACT FROM AUTHOR]