Application of remote sensing techniques to identify iron ore deposits in the Central Eastern Desert, Egypt: a case study at Wadi Karim and Gabal El-Hadid areas

Abstract

The integration of remote sensing, spectral measurements and field verification helped in discriminating new iron occurrences hosted in the metavolcanic rocks at Wadi Karim and Gabal El-Hadid areas in the Central Eastern Desert (CED) of Egypt. The iron host rocks were carefully recognized through different image processing techniques that were applied on Landsat-8 satellite image data with the implementation of the spectral signatures of the various iron minerals and host rocks. The detected iron ore is found in the form of Banded Iron Formation (BIF), veins and lenses of varied thicknesses ranging from a few centimetres to 5 m. They are composed mainly of magnetite and hematite, as well as accessories of aluminium, iron silicates and quartz. Moreover, the structure controls on iron ore occurrences were also illustrated in the investigated areas. The alignment of the iron forms with the primary and secondary structural planes of their host rocks may indicate the origin and mode of occurrence of the explored iron ore, as contemporaneous and syngenetic deposition with the solidification of the host metavolcanics. Several remote sensing techniques including Crosta principal component analysis (CPCA), constrained energy minimization (CEM) supervised classification technique and a newly proposed Landsat-8 band ratio (band6/band2) were applied for discriminating the iron-rich localities within the studied areas. These techniques showed high efficiency and applicability in the accurate delineation of the iron-enriched areas; this was validated through the field study.