District-scale mapping of Mississippi Valley-type Pb-Zn mineralisation potential through an AHP-TOPSIS model: a case study from the southern Hamedan area (western Iran)

The southern Hamedan area in western Iran is a region with high potential for Mississippi Valley type Pb-Zn mineralisation, for which a suitable prospecting map is needed to optimise future mineral exploration. Satellite imagery, geologic and geochemical data sets of the area were used to map Pb-Zn mineralisation potential using the analytical hierarchy process and the technique of order preference by similarity to the ideal solution (AHP-TOPSIS). Various criteria maps representing specific Pb-Zn criteria, such as lithological classes, structural controls, hydrothermal alteration, and geochemical anomalies in the Pb and Zn catchment basin geochemical anomalies, were integrated using the AHP-TOPSIS approach to obtain a final favourable map of Pb-Zn mineralisation in the southern Hamedan area. Fractal analysis was used to classify the final potential map into three zones: highly favourable, favourable, and slightly favourable. The four known Pb-Zn deposits are located in or adjacent to the highly favourable pixels. It is recommended that the unexplored highly favourable and favourable zones be considered for further exploration.