Volume 4, Issue 1

Analysis of Aeromagnetic Anomalies of the North-eastern Nigerian part of the Chad Basin

Kehinde Ishola1, Blessing Okoye2, Lukumon Adeoti3, and Kayode Oyedele4
1University Of Lagos, Akoka, Lagos, NIGERIA, 2University Of Lagos, Akoka, Lagos, NIGERIA, 3University Of Lagos, Akoka, Lagos, NIGERIA, and 4University Of Lagos, Akoka, Lagos, NIGERIA


An appraisal of aeromagnetic data lying between Longitudes 110 00' 25.95''E - 110 30’ 15.1”E and Latitudes 110 30’ 7.59”N – 120 05’ 45.6''N has been carried out with a view to understanding structural trends of interest as well as determination of depth to magnetic sources giving rise to magnetic anomalies in the study area. To achieve the objectives of this study, the datasets were digitized along contours, corrected for the main geomagnetic field, re-gridded, and merged to generate magnetic structural anomaly map of the area. Also, from the aeromagnetic data, we used spectral technique based on Fourier transformation to estimate depths along some selected profiles on the residual anomaly map. The results show that the most pronounced structures are observed towards the southern and central parts of the study area signifying that majority of the magnetic anomalies trend in the Northeast-Southwest while the minor ones trend East-West direction. This suggests that the study area is intensely fractured with major regional faulting systems playing important role in entrapment and exploration of natural resources as well as understanding the hydrogeologic framework of the basin. The spectral analysis shows mainly two depth magnetic sources, the deeper sources with depths in the range of 1.34 to 3.42 km while the shallow sources are observed at depths between 0.33 to 0.91 km. Aeromagnetic data analysis over the basin shows that prominent anomalies have been identified and located.

Keywords: Aeromagnetic data, Magnetic anomalies, Spectral analysis, Magnetic source, Fracture, and Basin

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