A large number of polymetallic deposits exist in the Takab-Baneh area, NW Iran. Different methods such as minimum noise fraction (MNF), pixel purity index (PPI), n-D visualization, mixture tuned matched !ltering (MTMF), relative absorption band depth (RBD), band ratio (BR), and principal component analysis (PCA) were used for extraction of alteration zone characteristics from ASTER data in the Takab-Baneh area. The overall accuracy of MTMF is around 97% for phyllic, and 98% for argillic propylitic, which vali- dates the potential and suitability of ASTER imagery for classi!ca- tion of alteration type. Subsequently, the alteration maps were con!rmed by ground-truthing, i.e., !eld observation and petro- graphic studies. The results show a wide distribution of three main phyllic, argillic and propylitic alteration zones, that can be considered as targets for future exploration in NW Iran.
