Alteration Zones Detection and Mineralization Potentialities of Gebel Monqul Area, North Eastern Desert, Egypt, Using Gamma Ray Spectrometry Data and Remote Sensing Techniques

Abstract

Exploration of mineral resources is a challenge for the future of economy and development in Egypt. While there are different geological metallogenic maps available, many of these mineral resources are not yet well mapped and defined. The technology and the new techniques of earth observations developed to capture images of the earth can be functioned effectively to determine the alteration zones containing economic mineral resources as well as defining their exact location and spatial extension. In this study, the Airborne Gamma Ray Spectrometry (GRS) data and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images have been applied illustrating the alteration zones and the characteristic minerals distributed at the Gebel Monqul area. Many types of hydrothermally alterations e.g; Kaolinitization, Serecitization, Hematization and Chloritization have been detected and differentiated from their host rocks of metavolcanics and plutonics. These alteration zones are characterized by significant minerals for each type of alteration. Kaolinite, Sericite, Hematite, Calcite, Alunite, Epidote and Chlorite are the main altered minerals observed in these zones. Integration of band selection, band rationing and Principal Component Analysis (PCA) techniques was used to clearly determine the lithological units cropping out in the study area. An automated lineament density map illustrating the distribution of the structures and fractures influenced in the area has been yielded, suggesting the channels and passages of the upcoming fluid minerals and consequent alteration zones as potential areas for mineral exploration. Lineaments reflect deformation zones involving secondary porosity; these zones are important channel-ways for the movement of hydrothermal solutions, which is the main reason for the existence of alteration zones being potential mineral resource areas.