The nonuniqueness of inverse solutions of a magnetic profile is well known. The example described here provides a useful insight into the interpretation of anticlinal structures which contain a continuous and uniform magnetic horizon. It also highlights the necessity of applying geologic control in the interpretation of such situations.
It must be made clear from the outset that the mathematical reasoning developed below applies to a geometric approximation to an anticlinal bed. The approximation is very good for a thin bed contained in a tight fold. It is less successful for a thick bed and for more gentle folding. Hence, only the thin bed is considered in any detail. Complications involving remanent magnetization, demagnetization, and large magnetic susceptibilities are ignored.