The Poshteh deposit is the first documented paleo-hydrothermal chimney-bearing volcanogenic massive sulfide (VMS) deposit in Iran. It occurs in the form of well-developed lensoid orebodies within the Eocene volcano-sedimentary sequence, and comprises of laminated, brecciated, banded, massive, and disseminated textures. The stratiform part of this deposit is approximately 500 m long and up to 20 m thick, and consists of massive to semi-massive sulfides and barites, some of which are banded, which are overlain by barite and siliceous exhalites. The stringer zone stratigraphically underlies the stratiform mineralization. Veins within the stringer zone are composed of quartz, barite, pyrite, galena, sphalerite, and chalcopyrite. Three thin layers of exhalative Mn–Fe-bearing chert overlies the sulfide–sulfate orebodies. Four types of fluid inclusions were recognized in barite and quartz encompassing monophase vapor, monophase liquid, two-phase liquid-rich inclusions, and two-phase vapor-rich fluid inclusions. The homogenization temperatures of fluid inclusions mainly vary between 86.2 and 241.9 °C, whereas their salinities focus on 0.99–21.23 wt.% NaCl equiv. The ore-forming fluids of the barite and quartz minerals are characterized by low-to-medium temperature and low-to-medium salinity. The δ³⁴S values of barite associated with the stratiform and stringer barite orebody range from 8.37 to 21.83 ‰, indicating that the sulfur was derived from the seawater. The sulfur isotope values of sulfide (− 5.18 to 9.33 ‰) are similar to those of VMS deposits from other parts of the world. The δ¹⁸O data suggest that the ore-forming fluids of the Poshteh deposit were mainly derived from deep subseafloor circulation of seawater. The well-preserved chimneys typically contain distinct concentric outer and inner sulfide- and axial sulfate-rich zones. The outer zones of the chimneys contain mainly pyrite and chalcopyrite. The sulfides within the inner zone consist predominantly of sphalerite, argentite, and galena. The axial conduits are commonly dominated by barite and calcite. The sulfide-rich chimney zones are also characterized by significantly higher metal contents. The presence of paleo-hydrothermal vent chimneys in the Poshteh Kuroko-type deposit and their trace-element contents also provides significant data for understanding the physicochemical conditions of VMS mineralization.

Poshteh矿床是伊朗第一个有记录的古水热含烟囱火山成团块状硫化物（VMS）矿床。它以始新世火山沉积序列中发育良好的类胶体矿体的形式出现，并且由层状，角砾状，带状，块状和散布的质地组成。该矿床的层状部分长约500 m，厚达20 m，由块状至半块状的硫化物和重晶石组成，其中一些是带状的，上面覆盖有重晶石和硅质的呼出气。纵梁带在地层上是层状矿化的基础。纵梁区内的静脉由石英，重晶石，黄铁矿，方铅矿，闪锌矿和黄铜矿组成。三层薄薄的呼出气含锰铁的石覆盖在硫化物-硫酸盐矿体上。在重晶石和石英中识别出四种类型的流体夹杂物，包括单相蒸气，单相液体，两相富液包裹体和两相富气液包裹体。流体包裹体的均质温度主要在86.2和241.9°C之间变化，而其盐度集中在0.99–21.23 wt。％NaCl当量。重晶石和石英矿物的成矿流体的特征在于中低温度和盐度中低。δ 重晶石和石英矿物的成矿流体的特征在于中低温度和盐度中低。δ 重晶石和石英矿物的成矿流体的特征在于中低温度和盐度中低。δ与层状和长条状重晶石矿体有关的重晶石的³⁴ S值范围为8.37至21.83‰，表明硫来自海水。硫化物的硫同位素值（-5.18至9.33‰）与世界其他地区的VMS矿床相似。该δ ¹⁸O数据表明Poshteh矿床的成矿流体主要来自深层海底海水循环。保存完好的烟囱通常包含不同的同心外部和内部富含硫化物和轴向的富含硫酸盐的区域。烟囱的外部区域主要包含黄铁矿和黄铜矿。内部区域内的硫化物主要由闪锌矿，银辉石和方铅矿组成。轴向导管通常以重晶石和方解石为主。富含硫化物的烟囱区的特征还在于金属含量明显更高。Poshteh Kuroko型矿床中存在古热液喷口烟囱及其微量元素含量，也为理解VMS矿化的理化条件提供了重要数据。