Spectral prediction of magnetic source depths from simple numerical models

Abstract

The depths to the top of buried magnetic sources may be inferred from the power spectrum of their field anomalies. Two examples using numerical models are presented to assess the reliability of the spectral depth estimation technique. The aeromagnetic field was derived from a computer simulation of magnetic anomalies generated by simple two-dimensional geological models. Mean depths to the geological models have been determined from two-dimensional spectral analysis of their aeromagnetic anomalies in map form. The results of the model studies show that the depths to the disturbing magnetic horizons can indeed be estimated from the spectral analysis of total magnetic field anomalies within a resolution limit of ±5%.