I have often fantasised about this. You would need a complete 3D model of a large crustal block (right down to 33 km depth) with information on the strength of every element. I can't see how you could gather that information, and even if you proposed to estimate it and sequentially correct the estimates, it would be a monstrous task. Maybe it will be possible one day. By comparison, the atmosphere is relatively simple - and even so in the UK the Met Office has the biggest computers in the whole country for their modelling work.