Geophysical Characterization Of Mineralization Potential Of Eastern Parts Of Ife-Ijesha Schist-Belt, Southwestern Nigeria.

An integrated approach which involve interpretation of Landsat ETM+, aero-magnetic and aero-radiometric data was undertaken over the eastern flank of Ilesa-Ijesha schist-belt, Nigeria, with an objective of delineating structural and lithological features that favour mineral deposition within the study area. The analysis of Landsat ETM+ data revealed four distinct lineament trending NNE � SSW, NNW � SSE, NWW � SEE and NE � SW. The lineaments density ranges between 0 and 2.67 m-2; higher over and around lithological contacts and areas underlain by felsic rocks. The application of analytic signal, tilt derivative and 3D-euler filters on aeromagnetic data allow identification of series of anomalies suspected to be lithological contacts, alteration zones, magnetic source anomalies and overall basement characteristics. The primary trend of structural features producing magnetic anomalies is generally NE � SW, which corroborate the Landsat ETM+ result. The analysis of radiometric datasets revealed geochemical information on potassium (K), thorium (Th) and uranium (U) concentrations, and results obtained was used to identify impacts from alteration and rock contacts and define bedrock lithology within the study area. The ternary-image generated form radiometric data interpretation show distribution of the radiometric intensity which correlated well with geological structures and lithology in the area.

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