Comparative Depth to Magnetic Source Analysis of Shanga (Sheet 96), Northwestern Nigeria Using Aeromagnetic Data

Abstract

The depth to magnetic sources and sedimentary thickness within the study area have been estimated using the recently acquired high-resolution aeromagnetic data (HRAD) of Shanga, sheet 96, north-western Nigeria, which is bounded by longitudes 4⁰ 3⁰' 00" E to 5⁰ 00" E and latitude 11⁰ 00' 00" N to 11⁰ 30' 00 N and covers approximately 3025 km2. To achieve the goals, three methods were used: the analytic signal method, the Euler deconvolution method and source parameter imaging (SPI). A range of depths between 11.457 m and 1314.409 m have been measured utilizing analytical signal and source parameter imaging techniques. The boundary between the research area's sedimentary basin and basement regions was made clear by the results of these two techniques, which were essentially similar. The study area's shallow sources are found in the east where outcropping basement rocks are present and the overburden thickness is minimal (0–71.968 m), whereas the deep sources are found in the southwest where the sedimentary cover is present and is rather thick (1314.409 m). There were four (4) for the 3D Euler solutions. Depths 200 m, between 200 and 400 m, between 400 and 600 m, and >600 m, but the most peculiar feature of all the Euler solutions is that solutions with shallow depths characterized the basement part of the study area while solutions with depths >600 m characterized the sedimentary portion of the study area. According to the maps, where the outcropping basement rocks could be found, the depths determined using the three methods were increasing towards the southwestern half of the maps and decreasing towards the eastern side.