Three ocean magnetotellurici data sets from sites on the Pacific plate are reinterpreted. The initial analysis found a correlation between the lithospheric age and the depth to a conductive zone beneath each site. That work also suggested that the resistivity increased below the conductor. This analysis, which includes new methods for constructing one-dimensional conductivity models, shows that the postulated increase in resistivity is not demanded by the data. It also reveals an unexpectedly large nonuniqueness inherent in the interpretation of these data. The previously reported trends with lithospheric age still exist, but they are not as strong as initially believed. Finally, it is shown rigorously that the different age sites are distinct in that no one-dimensional model can account for all three data sets.