Mapping and Depth Estimation of Magnetic Sources of the Chad Basin, Nigeria Using High Resolution Aeromagnetic Data

Kehinde S. Ishola; Olawale B. Olatinsu; Christopher E. Okagu; Olumide Omojola

doi:10.62292/njp.v35i2.2026.515

Authors

Kehinde S. Ishola
kishola@unilag.edu.ng

University of Lagos
Olawale B. Olatinsu
University of Lagos
Christopher E. Okagu
University of Lagos
Olumide Omojola
University of Lagos

Keywords:

Aeromagnetic, Magnetic Anomalies, Lineament, Depth to Source, Power Spectrum

Abstract

The Chad Basin is an intracontinental basin originated from the actions of a number of peripheral uplifts making a periodic study of this basin imperative. On this background, an aeromagnetic data of the Chad Basin was used to identify some magnetic anomalies and determine the depth of the magnetic sources. The residual map obtained from the application of first order polynomial fitting to the total magnetic intensity data, revealed two magnetic anomalies. The low frequency anomalies emanated from the deep seated bodies with thicker sediments and perceived to be the magnetic basement while the high frequency anomalies resulted from shallower geologic bodies regarded as the sediments cover. The lineaments map showed that the long regional trends that lie in the directions ENE–WSW, WNW–ESE and E–W control the subsurface structure beneath the studied area. The magnetic field amplitudes vary from a maximum of 223 nT to a minimum of 96 nT depicting varying magnetic highs and lows as possible indication of undulating basement surface and magnetic traps. The depth to the basement range from about 0.5 km in the south to 3.0 km and deepens towards the north. The energy power spectrum estimated an average depth to the top of regional sources is about 7 km while the shallow sources have an average depth of about 1.5 km to their magnetic sources.

Author Biographies

Olawale B. Olatinsu

Department of Physics/ Senior Lecturer

Christopher E. Okagu

Department of Geoscience/M.Sc student

Olumide Omojola

Department of Geosciences/M.Sc Student

Dimensions

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Mapping and Depth Estimation of Magnetic Sources of the Chad Basin, Nigeria Using High Resolution Aeromagnetic Data

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Keywords:

Abstract

Author Biographies

Olawale B. Olatinsu

Christopher E. Okagu

Olumide Omojola

REFERENCES

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