Application of hybrid AHP-TOPSIS method for prospectivity modeling of Cu porphyry in Varzaghan district, Iran

Varzaghan district is located in NW of Arasbaran magmatic belt (AMB) which is one of the most highly mineralized region in Iran and host to a significant number of porphyry Cu deposits such as Sungun Cu-Mo porphyry deposit. The main goal of this study is synthesizing diverse raster-based evidence layers including geochemical, alteration and geological geo-data sets for mineral prospectivity modeling (MPM). For this purpose, firstly, continuous values of six favorable evidential maps as main criteria (geochemical signature of PC1 scores, values of proximity to argillic, phyllic and iron-oxide alterations, values of proximity to Oligo-Miocene intrusions and fault density) were divided into reasonable classes by applying concentration-area fractal model and then discretized layers were integrated using analytical hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS) to generate a final map of porphyry Cu potential within the central part of Varzaghan district. Finally, the success-rate curve of the AHP-TOPSIS model as a quantitative evaluation method according to the locations of known Cu occurrences was drawn. Results revealed the successful performance of AHP-TOPSIS model in portraying the prospective areas related to porphyry Cu mineralization.