ANALYSIS OF HIGH-RESOLUTION AEROMAGNETIC DATA OVER PARTS OF SOKOTO BASIN, NORTH-WEST NIGERIA

Abstract

Sokoto Basin is one of the sedimentary basins suspected to have high hydrocarbon potential. Hence, due to the possible deposit of this economic mineral, it is worthy of being preliminarily investigated. This paper uses high-resolution aeromagnetic data over parts of Sokoto Basin covering longitude 4.00°E-5.00°E and longitude 12.00°N-13.00°N, to assess the sedimentary thickness beneath the subsurface while also establishing the basement topography. The studied area covered four adjacent one-degree sheets, namely, sheet 27 (Lema), sheet 28 (Argungu), sheet 49 (BirninKebbi) and sheet 50 (Tambuwal). Enhancement of the total magnetic intensity map was carried out to improve the anomaly characteristic of source bodies, and two-dimensional Spectral analysis was carried out using GEOSOFT software (Oasis montaj6.24 version) in order to estimate magnetic source depths in the area. The shallower sources occur at a depth range of 0.23 km - 0.79 km with an average depth of 0.47 km, while the deeper sources occur at a depth range of 0.83 km -1.95 km with an average depth of 1.40 km. The maximum depth to the top of the magnetic source body gets deeper around Lema and IllelaKwandu while the minimum depth is around Tambuwal, Danjema and Birnin-kebbi. Thedepth estimated from the spectral analysis compares reasonably well with the results from the Euler deconvolution. The areas with higher sedimentary thickness toward the northern part of the study area are feasible for hydrocarbon generation and are thus recommended for other geophysical surveys.Keywords: Sokoto Basin, sedimentary thickness, hydrocarbon exploration, high-resolution, aeromagnetic data,geophysical surveys