Interpreting marine magnetic anomalies in the Fourier domain

Abstract

Magnetic data play a key role in interpretation of deep sources, mostly when they are not easily investigable by other direct methods as in the case of oceanic crust. The most striking problem connected with magnetic data however, is due to their difficult quantitative interpretation that in final analysis derive from the mathematical properties of Laplace equation. Dipolarity increases these difficulties with respect to other potential fields as gravity, so that magnetic data are far from being interpretable “by eye”. The actual methods for reconstruction of crustal sources that reproduce or enhance magnetic observations will be shown, differentiated for 3D or 2D analysis, showing their benefits and/or their disadvantages if applied to marine magnetic data. We will show the results obtained applying a new linear inverse filter on a high-quality data set in the Tyrrhenian Sea, demonstrating the utility of Fourier 2D modelling when there is a large number of data to be interpreted.