In our method of determining depths from aeromagnetic profile data, several sampling intervals adapted to the possible ranges of depths are used for a preliminary analysis of the profiles. This step detects and locates all the anomalies. We then study each anomaly in detail, using several structural hypotheses such as bottomless prisms (dikes) and thin plates. In this way, we produce a series of theoretical structures for each anomaly; only the best-fitting ones are kept. Our results are shown as a distance-depth representation, with the symbols plotted so as to indicate the probable degree of realiability. The complete processing is done automatically by a computer and a plotter.