Subduction Zone: Relative motion with no friction


Can a tectonic plate slide beneath another with no friction?

This is a classic image that many get of a subduction zone but it is highly inaccurate in that because of the great weight of the continental plate, the ocean plate cannot slide easily with no friction.  It is the enormous friction that occasionally is released in great earthquakes. 


  • Heavy oceanic plate subducts beneath thicker, lighter continental plate
  • In reality there is enormous friction that locks the plates together
  • In reality the overlying plate gets pushed back and occasionally releases in great earthquakes