Evaluation of Aeromagnetic Data of Ilesha Area of Oyo State Nigeria using Analytical Signal (ASM) and Local wavenumber (LWN)

Abstract

This paper presents the analysis and interpretation of an aeromagnetic data of Ilesha area, (Sheet 243) sourced from Nigeria Geological Survey Agency. The area is located between 7.5^oN and 8.0^oN of latitude and longitude 4.5^oE to 5.0^oE. Two methods: Analytic Signal Method (ASM) and Local wavenumber (LWN) were used. These methods were used to process and analyse the data so as to generate the depth to magnetic sources as well as the source locations. The results obtained showed a shallower depth range limit for ASM between 0.348 km and 1.28 km, which is less than the result of LWN within the range of 0.478 km-1.51 km. The results also revealed more source locations in ASM result in comparison with LWN. The overall results of the methods have revealed the prospect of the lithology of the area for magnetic mineral exploration in the field of applied geophysics.

Keywords: Aeromagnetic survey, Analytic signal, Magnetic Anomaly, Local wave number, lithology