Interpretation of aeromagnetic data over some parts of Sokoto Basin, Nigeria, using source parameter imaging and 3D Euler deconvolution methods

Abstract

This investigation is aimed at determining depth to the bottom of magnetic source and to reveal some certain geological features across Sokoto basin using source parameter imaging and 3D Euler deconvolution techniques. The investigation employed fifteen number aeromagnetic sheets covering longitude 4°30'E - 6°00E and latitude 11°00'N - 13°30'N. The total magnetic intensity of the area was subjected to reduction to magnetic equator using a geomagnetic inclination angle of 1.4°, declination of 1.7° and a standard deviation of 0.1. Similarly, the total magnetic intensity was also subjected to regional - residual separation using polynomial fitting of the second order, of the least square method. Consequently, the total magnetic intensity and the reduction to equator revealed intensities ranging from -67.16 to 118.27 nT and -58.33 to 119.21 nT/m, respectively. Similarly, the results from 3D Euler deconvolution revealed depths of 1.38, 2.14, 2.58 and 2.80 km for structural indexes of 0, 1, 2 and 3, respectively. Finally, the source parameter imaging result revealed a maximum depth of 1.65 km and a minimum of 0.1 km in the study area. The implication of these results is that, even if other conditions are met, the possibility of hydrocarbon exploration in the basin may be very marginal. Key words: Aeromagnetic data, reduction to equation, Euler deconvolution, source parameter imaging, Sokoto basin.