Depth Estimation Based on Fourier Spectral Analysis of Potential Field Data
Authors: Ozegin KO, Alile OM
DOI Info: http://doi.org/10.5281/zenodo.5805122
The main purpose of using potential field data such as magnetic field data is to make available an enhanced knowledge of subsurface structural study. Depth estimation to magnetic anomalies often assists in mineral, groundwater and hydrocarbon explorations. The study deals with the quantitative interpretation of airborne magnetic data of Auchi sheet (Sheet No. 266), conducted by the Nigerian Geological Survey Agency. The average depth values to buried magnetic sources using the power spectrum of total intensity field were accomplished in parts of Edo north district of Edo State, Southern Nigeria using spectral analysis. These depths were established from the slope of the log- power spectrum at the lower end of the total wave number or spatial frequency band. The analysis of aeromagnetic data was construed using fast Fourier transform (FFT) in Oasis Montaj software. In order to reduce aliasing error, the aeromagnetic data was gridded at spacing of 2 km. It was showed from the radially average power spectrum depth estimated curve that, the depth to the magnetic sources in the area ranged from shallow 50 m to intermediate 200 m to deeper 1500 m. The variation in magnetic depth values shows common inclinations in the magnetic basement surfaces.
Affiliations: Department of Physics, Faculty of Physical science, University of Benin, Benin City, Edo State, Nigeria.
Keywords: Aeromagnetic Data, Basement, Filtering Functions, FFT, Magnetic Sources
Published date: 2021/12/30