Polar wander
![(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)
.](/Images/godic/202502/03/True_Polar_wander4705.jpg")
Polar wander is the motion of a pole in relation to a fixed reference frame. It can be used, for example, to measure the degree to which Earth's magnetic poles have been observed to move relative to the Earth's rotation axis. It is also possible to use continents as a static entity and observe the relative motion of the magnetic pole on the different continents; by doing so, the relative motion of those two continents to each other can be observed over geologic time.