Magnetic anomalies over thin plates and their analysis

The magnetic anomaly over a two-dimensional thin horizontal plate is similar to the first horizontal derivative of the magnetic anomaly over a thick dipping dike of infinite depth extent but with a different direction of magnetization. Hence, the magnetic anomalies of thin plates may be integrated along the profile and the pseudomagnetic potential anomaly thus obtained may be interpreted using any standard method of interpreting dike anomalies. Expressions for the Fourier amplitude and phase spectra of the magnetic anomaly over a thin plate are also derived and procedures to evaluate the parameters of the plate from the spectra are formulated.