Implementation of ASTER data for lithologic and alteration zones mapping: Derhib area, South Eastern Desert, Egypt

Abstract

Derhib area is dissected by narrow E–W-trending shear zones that delineate the alteration zones accommodating the infamous structurally-controlled talc mineralization in the South Eastern Desert of Egypt. A multidisciplinary remote sensing approach using ASTER images integrated with field data and petrographic investigations have been used for mapping the alteration zones at the Derhib area. Band ratios composites, band ratio, selective Principal Component Analysis (PCA) have been used for discriminating rocks and mineralization zones. Iron oxide/hydroxides-, phyllic and propyllitic-rich alteration zones were mapped using band ratios and selective PCA. Fuzzy logic modeling was implemented to integrate the most informative thematic layers for generating mineral prospectivity map. Based on eigenvector loadings, the map was produced by merging the selected PC thematic layers using fuzzy AND operator. The present study is consistent with the recent literature and shows the capability of fuzzy model as a valuable cost-effective tool to produce mineral potential maps, especially at the reconnaissance stages of mineral exploration.