The Pplates Virtual Earth project - how Pplates takes account of isostasy
This is an arbitrary test of the isostasy operator, stretching South America to removet he Arica Bend.
With topography classified to a mesh, the crustal thickness is originally estimated using a typical value of density for (continental or oceanic) crust and an internal reference column assumed to be in isostatic equilibrium.
Conservation of volume means that a change in a mesh face (triangle) area will result in an inversely proportional change in the estimated crustal thickness. The topographic altitude of the old crustal thickness and that of the new crustal thickness are each calculated isostatically by comparison to the reference column. The difference in altitude is then added to the old altitude value.
Pplates is designed and built by Dr Joe Kurtz and Professor Gordon Lister.