Polar wander

True polar wander represents the shift in the geographical poles relative to Earth's surface, after accounting for the motion of the tectonic plates.

This motion is caused by the rearrangement of the mantle and the crust in order to align the maximum inertia with the current rotation axis[2] (fig.1).

One proposed solution to account for this imbalance is that if the difference between the maximum moment of inertia and rotation axis exceeds a certain limit, the planet will undergo a larger degree of oscillation to realign its maximum of inertia with its rotation axis.

If this is true, then models predict that the shell could display the polar wander trace on its surface as its crust realigns.

These models have been defended by evidence from features on the side facing away from Jupiter that appear to have shifted up to 80° away from their initial positions of formation.

Magnetic North Pole Positions
(Fig.1),Dark patch represents denser material falling inward, light patches represent lighter material that rises through the mantle. Initially, they are offset from the pole or the equator, but the mantle and lithosphere slowly wander in order to align those features with the natural bulge at the equator (or the depression of the pole) .
(Image adapted from Steinberger & Torsvik, 2008) .