Sediment hosted stratiform barite – (Cu-Zn-Pb) deposits in the southwest Mahabad, Iran; implications for geology, ore textural, compositional, and S-O isotopes geochemistry

[Display omitted] •The Precambrian-aged metasedimentary succession, located in the SW Mahabad, NW Iran, hosts several sediment hosted stratiform Ba-(Pb-Cu-Zn) deposits.•This investigation is focused on three main ore deposits including Meraneh, Sorkhab, and Shekarbeig that have higher barite than sulfides.•Textural evidence together with trace elements distribution and isotopic investigation in the stratiform, massive, and stockwork ore zones signify that the SEDEX-type mineralization has been occurred in this district.•Textural and isotopic evidence imply a diagenetic origin for stratiform mineralization that subsequently overprinted by the hydrothermal event. The southwestern part of Mahabad town in the northwestern part of the Sanandaj-Sirjan metamorphic zone (SSZ) of Iran hosts seven barite-base metal deposits. They have occurred within the Precambrian-aged metasedimentary succession including black color fine-grained shale, slate, and phyllite with minor calcareous intercalation. This investigation is focused on three main ore deposits including Meraneh, Sorkhab, and Shekarbeig. The mineralized units and host rocks have been metamorphosed to lower greenschist facies in the Post-Cretaceous. Five different stages of mineralization were distinguished based on the field observations, mineralogical and textural relationships, morphology of the orebodies, and mineral chemistry studies. The followings are the stages of evolution: (1) precipitation of framboidal, colloform, and monomineralic pyrite bands and fine-grained barite (2) stratiform accumulation of barite with sulfide and un-mineralized sediment strata (3) stockwork mineralization and associated alteration (4) formation of discrete vent complex associated with massive sulfides and barite in replacement zone, and (5) post-mineralization deformation and shearing process, contemporaneous with regional metamorphism. Pyrite, chalcopyrite, sphalerite, and galena are the major sulfide minerals, in order of abundance, found in the studied deposits, accompanied by the minor amounts of tetrahedrite and covellite. The stratiform, massive and stockwork ores are indicative of the main ore-forming event and are volumetrically the most important facies. The electron probe micro-analyzer (EPMA) data of sulfide minerals indicates a distinct variation in trace element concentrations during the ore formation. Besides, this study focuses on distributions of δ 34S value in sulfide minerals, as well as δ 34S and δ 18O va