Earth's surface is a very active place; its plates are forever
jiggling around, rearranging themselves into new configurations.
Continents collide and mountains arise, oceans slide beneath
continents and volcanoes spew.
http://theanalystmagazine.com/pr/n302.html
As far as we know Earth's restless surface is unique to the planets in
our solar system. So what is it that keeps Earth's plates oiled and on
the move? Answers this ...