Fig. 6
From: The (Paleo)Geography of Evolution: Making Sense of Changing Biology and Changing Continents
Cartoon of inertial interchange true polar wander after Meert (1999). In the special case of IITPW, the maximum and intermediate axes of inertia interchange (Iint becomes Imax and vice versa). The result is that the mantle + lithosphere tumble through 90 degrees. The total time for this reorganization can be as short as 15 million years and could result in drastic changes in paleogeography in a short period of time. (ω = rotation axis, Imin = minimum inertial axis, Iint = intermediate inertial axis, and Imax = maximum inertial axis)