Abstract: The Mahin area is a part of Tarom- Hashtjin zone that
located in west of Qazvin province in northwest of Iran. Many copper
and base metals ore deposits are hosted by this zone. High potential
localities identification in this area is very necessary. The objective of
this research, is finding hydrothermal alteration zones by remote
sensing methods and best processing technique of Advanced
Spaceborne Thermal Emission and Reflection Radiometer (ASTER)
data. Different methods such as band ratio, Principal Component
Analysis (PCA), Minimum Noise Fraction (MNF) and Least Square
Fit (LS-Fit) were used for mapping hydrothermal alteration zones.