REMOTE SENSING INVESTIGATION OF LI-BEARING PEGMATITES AT EWOYAA, SOUTHERN GHANA

As the world moves toward cleaner energy sources and sustainable transportation, the demand for lithium in rechargeable batteries for electric vehicles, laptops, mobile phones, digital cameras and other uses will continue to increase. The Ewoyaa lithium mine in Ghana, West Africa, with ore reserves of 25.6 million tons, and a life expectancy of 12.5 years is supposed to start production in the second quarter of 2025. The mining area lies within the Cape Coast Basin, a Proterozoic volcano-sedimentary basin, part of the Early Proterozoic Birimian Supergroup. Several granitoids plugs consisting of tonalite to peraluminous granite, intrude the metasediments. The area is intruded by subvertical pegmatite dikes with the mineralization units ranging from 30-100 m in thickness. In this study, remote sensing data consisting of ASTER, Landsat OLI, Worldview-3 and DEM are processed and used to assess their effectiveness in mapping the mineralized pegmatites and associated hydrothermal alteration zones from the surrounding rocks. Techniques include RGB combinations, band ratioing, Principal Component Analysis (PCA), supervised classification, and spectral unmixing. Additionally, airborne magnetic and radiometric datasets are processed and used to interpret the geology and geological structural patterns contributing to the potential mineralized zones.