Officials in Japan now confirm that liquefaction took place during the 9.0 quake.

This added to the destruction.  Roads, power poles and buildings were damaged directly by liquefaction.

Liquefaction is a major concern in the United States along the New Madrid fault line.  There is evidence, and reports of liquefaction during a series of strong quakes during the 1800s.

Liquefaction causes solids, like sand, to act like water.  It happens when great pressure is applied, as in the case of an earthquake.