Geological Mapping and Economic mineralization prospectivity by Remote Sensing and GIS-based Integration around Keleltu Say Area, West Guji Zone, southern Ethiopia

Abstract

In recent years, various geological activities different economic mineral prospecting, and exploration programs have been intensified in different parts of Ethiopia to reveal the geological maps and to evaluate mineral potentials. This study is therefore aimed at testing the viability of using remote sensing and geographic information system (GIS) techniques for geological mapping and prospecting for economic mineralization in the study area. Different digital image processing techniques were applied to Landsat-8 Operation Land Imager (Landsat-8/OLI) image to increase the discrimination between various lithological units and to delineate wall rock alteration which represents a potential zone of economic mineralization. Remote sensing methods included; banded combination, band ratios, and lineament extractions to clarify different structures in the study area. Geochemical analysis for mineralized samples followed by Pearson correction matrix of the chemical data gave a strong correlation between Fe2O3, TiO2, Na2O, and MnO indicating that their mode of delivery in the area could be similar, with a likely source from hydrothermal fluids in the area. The results confirmed the findings from remote sensing studies on hydrothermal alteration which could be an indication for economic mineralization. The enhanced satellite images were implemented in the GIS environment to facilitate the final production of the geological map at a scale of 1:50,000.  It was therefore concluded that integration of remote sensing techniques and geological field mapping provide a tool for delineating economic mineralization in the rocks of the study area.