The world-class Mehdiabad nonsulfide deposit consists of several accumulations of Zn–Pb–Fe nonsulfide minerals, derived from supergene of a vent-proximal sub-seafloor replacement SEDEX-type deposit hosted in lower Cretaceous clastic–carbonate rocks of the Taft and Abkuh Formations. The main sulfides are galena, sphalerite, pyrite, and minor amounts of chalcopyrite, which have been partially or completely transformed into nonsulfide minerals by supergene processes. Currently, the Zn mineralization in the Abkuh Formation (ore horizon II) is almost fully oxidized: the Mehdiabad deposit which can be assigned to both direct replacement and wall-rock replacement types. The time of the formation of the nonsulfide deposit has not been determined, but it is probable that the main supergene metallogenesis happened during Tertiary, possibly between post-Cretaceous to present. The mineralogy of the nonsulfide mineralization is generally complex and consists of smithsonite, hydrozincite, and hemimorphite as the main economic minerals, accompanied by cerussite, anglesite, iron–manganese oxy-hydroxides, sauconite, and Zn-rich clays. Commonly, nonsulfide minerals in this deposit consist of two types of ore: red zinc ore (RZO), rich in Zn, Fe, Pb-(As), and white zinc ore (WZO), typically with very high zinc grades but low concentrations of iron and lead. The proposed three-step scenario for the deposition of nonsulfide mineralization in the Mehdiabad deposit comprises: (1) the deposition of primary sulfides contemporaneous with lower Cretaceous clastic–carbonate host rocks to form SEDEX-type mineralization; (2) during the Late Cretaceous to present, regional uplift leads to deformation, folding, and thrusting of sulfide-bearing lower Cretaceous sequence; and (3) as a result, Zn–Pb–Fe sulfides hosted in carbonates experienced oxidation under an arid-warm climate to form the supergene nonsulfide ore mineralizations.

世界一流的Mehdiabad非硫化物矿床包含Zn-Pb-Fe非硫化物矿床的几处堆积物，这些矿床是塔夫脱和塔布组的下白垩统碎屑碳酸盐岩中的近海底海底置换SEDEX型矿床的超基因。 。主要的硫化物是方铅矿，闪锌矿，黄铁矿和少量的黄铜矿，它们已通过超基因过程部分或完全转化为非硫化物矿物。目前，Abkuh地层（地平线II区）中的Zn矿化几乎已被完全氧化：Mehdiabad矿床可分为直接置换和围岩置换两种类型。尚未确定非硫化物矿床的形成时间，但是主要的超基因成矿可能发生在第三纪，可能在后白垩纪到现在之间。非硫化物矿化的矿物学通常是复杂的，由铁矿石，水锌矿和半变石为主要经济矿物，并伴有铜铁矿，角铁矿，氢氧化铁锰锰酸盐，锌铁矿和富锌粘土。通常，该矿床中的非硫化物矿物由两种类型的矿石组成：富含锌，铁，铅（As）的红锌矿（RZO）和白锌矿（WZO），通常锌品位很高，但浓度低铁和铅。拟议的Mehdiabad矿床中非硫化物矿化沉积的三步方案包括：（1）与白垩纪下层碎屑碳酸盐岩宿主岩同时发生的一次硫化物的沉积，形成SEDEX型矿化；（2）在白垩纪晚期到现在，局部隆起导致含硫化物的下白垩纪层序变形，褶皱和逆冲；（3）结果是，在干旱温暖的气候下，碳酸盐中所含的Zn-Pb-Fe硫化物经历了氧化，形成了上原非硫化物矿化。