Application of Aeromagnetics as a Basin Depth Discriminating Tool Prior to Seismic Exploration: A Case Study of Central Niger Delta, Nigeria

Abstract

Eight aeromagnetic maps and high resolution softcopy aeromagnetic data of the same area with available drilled well depth data were used for subsurface depth investigatuion in the Central Niger Delta, Nigeria. The data was processed, filtered and transformed to other grids using either Oasis Montaj  and/or USGS potential field software with their associated extension  packages. Anomaly Separation, Spectral Analysis, Euler Deconvolution, Horizontal Gradient Magnitude were done using the relevant softwares.The results of  spectral analysis, euler deconvolution and horizontal gradient depth maps generated clearly indicates that the well bottom (well B) depth of 3.234km compared with the different thematic magnetic basement depth from spectral 4.2km, Euler 6.421km, and HGM 4.0kmis effective in basement depth discrimination. The result show a unique closeness in comaparism  between already drilled depth with interpreted magnetic depth results. This indicate that the method can be reliable as a basin depth determining tool in virgin  sedimentary basins prior to seismic exploratioin.