Our research investigates the control of stylolites on fluid flow in dolostone host rocks in the Irankuh Zn-Pb world-class deposit located in Sanandaj-Sirjan Zone, Iran. Core samples from the north flank of this zone, originating from the Gushfil, Rowmarmar, and Tappehsorkh mines, were examined (macro- and microscopically) with respect to the different types of stylolites and their relationship to mineralization. The stylolites are mostly suturedwith sharp peaks with simplewavy-like outlines. Tectonic stylolites are increasing in number toward ore intervals while burial stylolites usually occur in fine dolostones and clearly relate to the type of lithology. The stylolites in Irankuh often act as flow conduits which became enriched in residue solid hydrocarbon and in ore minerals (sphalerite and galena) toward intervals enriched in ores. The associated re-activation of stylolites resulted from tectonic forces and bulging. In conjunction, the injection of overpressured fluids formed intensely fractured and hydrothermal brecciated dolostone corridors. The abundance, typology, and re-activation of stylolites in Irankuh with respect to the tectonic regime support an epigenetic origin, which contrasts with the syn-sedimentary origin proposed in literature. The results presented in this study can aid in the prospection of similar ore deposits elsewhere.

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