In 1976 M.W. Mahaffy published a basic ice-sheet model which did not make the usual steady-state assumption of constant height and which allowed for time-varying ice accumulation rates. For this reason his model should be of interest to creation researchers, who can use it to model the rapid growth of post-Flood ice sheets. This paper provides a brief overview of the theory and assumptions behind Mahaffy’s model and its solution. The model is used to simulate the rapid growth of a long but thin isothermal ice ridge. The results are then compared with the results from the Vardiman model. A suggested technique for using the Dansgaard-Johnsen and Mahaffy ice sheet models to estimate annual layer thicknesses near an ice divide is also presented.