“…A great variety of 1-D modelling and inversion schemes exist (Niblett and SaynWittgenstein, 1960;Wu, 1968;Jupp and Vozoff, 1975;Jones and Hutton, 1979;Parker, 1980;Parker and Whaler, 1981;Fischer et al, 1981;Hobbs, 1982;Constable et al, 1987;Meju, 1988Meju, , 1992Meju and Hutton, 1992).…”