Making the simulator

The TGEA model earth would be a basic dts sphere. It would then have some curved meshes (dts objects) mounted to on it to simulate the shifting continental plates. The model earth and moon would respond to real game physics for gravity to simulate an orbit. The dts mesh plates would also respond to the gravitational pull of the sun and moon. In the TGEA simulation, the sun could simply be a fixed gravitational spot (and source of light).

Some plates are known to be on top, and others to be on the bottom where they meet, so this is kind of important. To do it right, the tectonic plate meshes would need to have collision detection much better than a simple bounding box. It can't be built to actual scale (distance between a scaled down version of the earth and moon is too great for a basic TGEA map), and the physics can only approximate the real pull... but a basic approximation of the theory could be done.
Earth Plate.