Comparison of ASTER and ETM+ data for exploration of

Sar Cheshmeh area is located in the Central Iranian Volcanic Belt. The area is covered mainly by the Eocene volcanic rocks that are intruded by the Oligo-Miocene intrusives. Copper mineralization in the area is mainly of porphyry type and is associated with extensive hydrothermal alteration. ETM+ and ASTER data has been analyzed for enhancing the areas with hydrothermal alteration through principal component analysis and Crosta technique. For each data set, iron oxide and hydroxyl images are prepared. The comparison of these images for ASTER and ETM+ data on this study area showed that ASTER data has better capability for recognition of hydrothermal alteration and lithological discrimination