Delineation and Correlation of Lineaments Using Landsat-7 ETM+, DEM and Aeromagnetic Datasets: Basement Complex of Shanono, Northwestern Nigeria

Abstract

An integration of Landsat-7 ETM+, DEM and aeromagnetic datasets was used for basic surficial geologic mapping of the area of study. False colour composite and principle component analysis were derived from three separate bands each with same spatial resolution of 30 m, superimposed over one another. Visible and infra-red waves of the electromagnetic spectrum were sent out to the surface/near surface and the received impulses reveal areas with varying magnetic susceptibilities, displayed on the first vertical derivative map and areas that emitted ranges of heat radiation signatures, displayed on the analytical signal map. Lineaments were conversely extracted from these maps over an area of about 770 km2. These lineaments represent fractures, faults, discontinuous quartz ridges, river channels, trenches and furrows in field. The eastern major fracture is the Kalangai major fault trending NE-SW. However, a possible presence of a mega fracture structurally controls River Karaduwa with other tributaries trending NW-SE, almost N-S. Part of the area also possesses gold mineralization potentials along the deep seated Kalangai major fault. The lineaments yielded from both datasets were integrated and showed a coincide results of the rate of deformation that most have affected the area to be of brittle/ductile form. The aeromagnetic data exhibits evidence of near surface fractures while the remote sensing data revealed more of surface fractures. Rose plots where inculcated and showed the dominant trend directions of the lineaments to be NE-SW and NW-SE.