Abstract: Enhanced Thematic Mapper Plus (ETM+) and airborne geophysics data have been used for locating porphyry copper and epithermal gold prospect areas related to hydrothermal alteration zones in the Lut block of eastern Iran. The Lut block has a great potential for different types of mineralization due to its extensive exposure of Cenozoic volcanic and subvolcanic calc-alkaline rocks generated in a subduction zone tectonic setting. Various ETM+ images processing techniques were employed, including false color composite images, color composite ratio images, standard PC image analysis on six bands and color composite selective PC images. Application of these techniques detected four major prospect areas and also identified another small previously unknown alteration area in the southeastern part of the district. Color composition selective PC images proved to be the most reliable method for exploration. Airborne magnetometry data show high magnetism over the most of the study area, resulting from the presence of magnetic-series granitoid rocks and/or propylitic/potassic alteration zones with magnetite veins related to mineralization. Low magnetic areas reflect intense magnetic destruction in other types of alteration zone. Radiometry detected areas of high K and U counts that have resulted from the presence of sericite, clay minerals and K-feldspar in alteration zones with low magnetism.

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