Mapping hydrothermal alterations and associated lineaments within Kaiama, north-central Nigeria, using Landsat 8 Operational Land Imager Data and Digital Elevation Model /Levantamiento de mapas de alteraciones hidrotermales y lineamientos asociados al interior de Kaiama, norte central de Nigeria, con information del satelite Landsat 8 Operational Land Imager y Modelos Digitales de Elevation

• Published in: Earth sciences research journal 2023-12, Vol.27 (4), p.367
• Main Authors: Ohiani, Umaru Aliyu, Okunlola, Olugbenga, Danbatta, Umaru Adamu, Olisa, Olusegun G
• Format: Article
• Language: English
• Subjects: Analysis; Clay minerals; Earth resources technology satellites; Gneiss; Hydroxides; Image processing; India; Iron compounds; Iron oxides; Mineral industry; Mining industry; Nigeria; Ore deposits; Rationing; Remote sensing; Tectonics (Geology)
• ISSN: 1794-6190
• DOI: 10.15446/esrj.v27n4.107002

This research focuses on the geological investigation of Kaiama region, which is characterized by a diverse range of rock formations, including mylonites, porphyritic granites, gneiss, schist, phyllites, and pink granites. The study employs remote sensing techniques, utilizing Landsat 8 OLI data and Digital Elevation Models, to systematically map the spatial distribution of hydrothermal alterations and tectonic structures associated with mineralization in the Kaiama area. Various image processing methods such as Color Composites, Band Rationing, and Principal Component Analysis (PCA) were employed to extract valuable information from the collected datasets. Utilizing Sabins band ratios (4/2, 6/7, and 6/5), we categorized alterations associated with iron oxides, clay minerals, and ferrous minerals. PCA was applied to refine the identification of alteration zones, using two distinct sets of images: H-image (comprising bands 2, 4, 5, and 7) and F-image (comprising bands 2, 5, 6, and 7), which represented iron-oxide and hydroxyl mineral deposits, respectively. The synthesis of H, F, and H+F images in RGB format provided an optimal representation of the spatial distribution of hydrothermal alterations, exhibiting a strong positive correlation with known mining regions for gold, copper, wolframite, and tantalite within the study area. Furthermore, a comprehensive analysis of regional lineaments revealed a consistent NNE-SSW to NE-SW correlation, suggesting a predominant control on mineralization trends. This study advocates for adopting remote sensing techniques, specifically Landsat 8 data and DEM, as an effective approach for mapping hydrothermal alterations and identifying key structural controls associated with mineralization. Keywords: Band Ratio, Principal Component Analysis, False Colour Composite, Landsat 8 OLI, Kaiama Este trabajo se enfoca en la investigation geologica de la region de Kaiama, la cual se caracteriza por un rango diverso de formaciones rocosas que incluyen milonitas, granitos porfiriticos, gneises, esquistos, filitas y granitos rosa. El trabajo emplea tecnicas de teledeteccion, con information del satelite Landsat 8 OLI y Modelos Digitales de Elevacion, para levantar un mapa de la distribucion espacial de las alteraciones hidrotermales y las estructuras tectonicas asociadas con la mineralization del area de Kaiama. Se emplearon varios metodos de procesamiento de imagenes como Falso Color Compuesto, Reduction de Bandas, y Analisis de Comp