Analysis of aeromagnetic data for subsurface structural features hosting minerals of Sumaila Local Government Area (L.G.A.) of Kano State, Northwestern Nigeria.

Abstract

Magnetic anomalies are frequently caused by lava flows, faults, dykes, and other natural phenomena. In regolith research, the magnetic method is a powerful tool that can be used effectively. Because the technique offers a helpful indicator of lithology, structure, weathering, and alteration processes in addition to a reasonably direct mapping of the abundance of magnetic minerals. The present study analyzes aeromagnetic data for the geologic and structural characteristics of Sumaila, a local government area in Kano, Nigeria. The area under study contains indicators such as faults, fractures, and contacts that are significant in mineral exploration. Aeromagnetic data was acquired from the Nigerian Geological Survey Agency (NGSA). The data was subjected to various analyses and processing such as regional/residual separation, reduction to the equator (RTE), vertical derivatives (VD) (First & Second), and analytic signal (AS) using the Oasis Montaj software. Regional/residual separation revealed an NE-SW trend of the magnetic anomalies. The residual anomalous map contains low amplitude field values between -75.7nT and 93.2nT. The FVD map shows a smooth, shallow magnetic body comprising positive and negative magnetic signatures ranging between -0.20nT/m and - 0.17nT/m. The SVD map shows an irregular magnetic signature of low amplitude with values from -0.00151nT/m to 0.00154nT/m. The analysis of vertical derivatives revealed magnetic structures that depict shear zones and possible zones of mineralization. The AS map indicates magnetic anomaly edges and their source positions with values 0.01nT/m to 0.32nT/m. Three major features are isolated: the first cuts through Bunturu, Retsida, and Ringi, the second lies through Gangadugu and Farin Dutse, while the last passes through Gandama Gandarma, Wayo, and Birnin bako.