Magnetic-anomaly Fourier spectrum of a 3D Gaussian source

I obtain a closed-form expression for the total-field magnetic anomaly generated by a 3D Gaussian magnetization distribution. The solution is evaluated by a novel contour integration in the complex-wavenumber domain. The spatial-domain solution is then computed by a numerical inverse Fourier transform. This calculated field can be used to interpret magnetic data because a 3D Gaussian function can represent a compact and smooth source. The method, moreover, allows for calculation of the Fourier components as a function of the distance between the depth of the source and the height of the observation level. The solution is thus useful for the inverse problem, spectral analysis, or data continuation. © 2005 Society of Exploration Geophysicists. All rights reserved.