Hydrothermal Altered Mineral Deposits Mapping Using Landsat- 8 OLI Images in Taftan 1:100,000 Geological Sheet, Iran

Evaluating the conventional methods for mapping hydrothermal altered deposits by using landsat-8 OLI images in the Taftan one to one hundred thousand geological Sheet is the prime target of our study. We used the color composite, band ratio, principal component analysis. The color composite and band ratio methods showed very clearly the hydrothermal altered deposits of clay minerals, iron oxides and ferric oxides around the fumaroles. The principal component analysis also enabled us to represent undoubtedly the altered hydroxyl and iron oxide mineral deposits of this region concentrating around the fumaroles. Finally the target detection method for reference spectral analysis by using EnvI 4.8 detected the representative hydrothermal altered minerals around study area. Therefore, all the methods showed high efficiency for mapping hydrothermal altered mineral deposits.

Keywords:

Taftan , Hydrothermal Alteration , OLI , Band Ratio , PCA