ASTER Spectral Analysis and Lithologic Mapping of Qa’le Hasan Ali Quaternary Volcano in Central Iran

This study focuses on results derived from satellite image processing of the Qa’le Hasan Ali Quaternary crater, located in Central Iran, utilizing ASTER data. Band Ratio, Spectral Angle Mapper, Principal Component Analysis, Minimum Noise Fraction, Support Vector Machine and Random Forest techniques were used for mapping various rocks, and minerals in this area. The color composites from the band ratios (B5, B6, and B8), the PCA transform technique on bands 1, 2, 5, and 8 and 1, 3, 4, and 6 (visible, NIR and SWIR) of ASTER data show distribution of different rocks and minerals. The SAM result displays an acceptable matching with mirabilite, gypsum, calcite, dolomite, aragonite minerals, and epidote and chlorite as well. The RF and SVM algorithms show an improvement in the classification of related lithology in the study area. The lithologies enhanced by ASTER data showed excellent match with field evidence, petrographic studies, and the available geologic map. The distribution haloes of the volcanic craters are aligned with field observations. The confuse matrix and the overall accuracy yield 89.15% for SVM compared to 84.41% accuracy for RF classification. Previous geochemical and isotopic published data indicate this Quaternary volcano contains xenoliths with carbonatite affinities and potential for rare earth elements. Further studies are recommended to explore the potential for REE deposit in the area and to expand the application of these methods to other volcanic craters in the region.