Comparison of ASTER and ETM+ data for exploration of porphyry copper mineralization: A case study of Sar Cheshmeh areas, Kerman, Iran  H. Ranjbar, H. Shahriari Department of Mining Engineering, Shahid Bahonar University of Kerman, Iran. Post box No. 76135-133, Tel and Fax: +98-341-2112764 Email: hranjbar64@yahoo.com M. Honarmand Department of Geology, Shahid Bahonar University of Kerman, Iran. Post box No. 76135-133 Introduction The study area is located in the southern part of Central Iranian Volcanic Belt. This belt has a great potential as far as porphyry copper mineralization is concerned. Darrehzar and Sar Cheshmeh porphyry copper deposits are presently mined for Cu, and Mo in the area. The area has a semi-arid type of climate and has a mountainous topography. Vegetation cover is substantially poor in the area. Porphyry type deposits are associated with hydrothermal alterations such as phyllic, argillic, potassic and propylitic. Hydroxyl minerals are abundant in the phyllic, argillic and potassic zones. At the same time, an oxide zone is developing over many of the porphyry bodies, which are rich in iron oxide minerals. These alteration minerals can be detected by remote sensing techniques. Hydroxyl and iron oxide minerals can be identified through remote sensing techniques (e.g. Rutz-Armenta and Prol-Ledesma, 1998; Tangestani and Moore, 2001). Landsat data has been used for a number of years in arid and semi-arid environments to locate areas of iron oxides and/or hydrous minerals which might be associated with hydrothermal alteration zones. ASTER sensor onboard Terra platform has more capability in terms of spatial and spectral resolution than Landsat. Theoretically, the SWIR bands of ASTER have more capability than the landsat for recognition of areas with hydrothermal alteration(Figure 1). This study aims at evaluating ASTER and ETM+ data for enhancing the areas with hydrothermal alteration. Different workers have used ASTER data for geological mapping in recent years(Danishwar, 2001; Abdeen et al., 2001; Rowan and Mars, 2001 ; Abrams, 2002; Liu and Mason, 2002, Yoshiki, N., 2002) .  Figure 1: A) Spectra of hydroxyl bearing minerals(after Hunt, 1979). Bandwidths of TM and ASTER are shown. B) Relative reflectance for ASTER bands over an altered area. |