Multiscale mineralogical investigations for mineral potentiality mapping of Ras El-Kharit-Wadi Khashir district, Southern Eastern Desert, Egypt

Abstract

Through various scales of observation, ranging from remote sensing data, field investigations, hand specimens, microscopic petrographic examinations, XRD, to SEM, indicators of various mineralization types are highlighted in Ras El-kharit-wadi Khashir (Eastern Desert, Egypt). Systematic remote sensing exploration of the mineralized zones is performed through integrating Sentinel 2 and ASTER datasets. False-color combinations, informative band ratios, relative absorption band depth, and CEM techniques were applied to discriminate rock units and various types of hydrothermal alterations. Moreover, ALOS PALSAR DEM was utilized to decipher the structural lineaments. Intensive field investigations confirmed hydrothermally altered zones that were picked out through remote sensing analysis and revealed that the study area is affected by cataclastic metamorphism to some extent. Magmatic and metamorphic rock types are represented by propylitic, phyllic, argillic, and silicification zones. Sericitization, chloritization, epidotization, kaolinitization, carbonatization, and silicification are recorded utilizing petrographic and remote sensing investigations. Moreover, the current study reveals that the detected alteration is the main reason for the apparent wide range of petrographic characteristics of each rock type and bearing several opaque minerals, such as pyrite, magnetite, titanomagnetite, chalcopyrite, arsenopyrite, covellite, galena, goethite, and hematite. Most of these opaques were identified using ore microscopy, XRD, and SEM. The distribution of hydrothermal alterations, representative samples bearing mineralization, structurally dissected zones are integrated to build a mineral potentiality map of the study area. The resultant MPM was confirmed via field survey and emphasized the usefulness of the current integrated approach besides highlighting about 125 km2 as potential mineralized zones.

Keywords

• Sentinel 2
• ASTER
• Hydrothermal alteration
• Ore mineralogy
• Eastern desert