Ultra-Fast 3D parameterised AEM inversion using spectral methods

One of the first usages of spectral methods in EM was by Peter Annan in development of the algorithm for EM modelling program "PLATE", popular in the days of mainframe VAX computers. Using recent developments in spectral methodology and parallel computing on GPU boards, it is predicted to be possible on a desktop to run geologically plausible AEM forward models in microseconds, and inversions in milliseconds. In practice, the limitations of noise, imperfectly known waveforms, coupled with the effects of dielectric permittivity, viscous magnetism (superparamagnetism) and induced polarization conspire to limit the accuracy and speed of the process.