Hydrothermal alterations mapping using Quickbird and Landsat-8 data, a case study from Babbiduyeh, Kerman province, Iran

In this work, we focus on investigating the Quickbird and Landsat-8 datasets for mapping hydrothermal and gossans alterations in reconnaissance porphyry copper mineralization in the Babbiduyeh area. This area is situated in the Central Iranian Volcano-sedimentary Complex, where large copper deposits like Sarcheshmeh as well as numerous occurrences of copper exist. The alteration zones are discriminated by implementation of band ratio and principal component analysis on the Quickbird and Landsat-8 datasets. The image processing results are evaluated by field surveys, X-ray diffraction (XRD), microscopic thin section, and spectroscopic studies of field samples as well as the 1:100000 Sarduiyeh and 1:5000 Babbiduyeh geological maps. In addition, the spectral characterizations of the samples are analyzed by visual inspection, and the PIMAView, SAMS, and ViewSpecpro software programs. The combined spectroscopic measurements, XRD analyses, and petrographic studies revealed mineral assemblages typical of the phyllic, phyllic-supergen, propylitic, argillic, and gossan alterations. The results obtained from image processing and analysis of field samples illustrated examples of effects of iron oxides and hydroxides on the surface of phyllic and argillic alterations. Hence, it can be concluded that the areas discriminated in Quickbird as gossans correspond to the phyllic and argillic alteration areas.