Liquefaction

Liquefaction is a process where solid material, usually soil, behaves like a liquid.  This typically occurs during an earthquake when intense shaking causes loosely packed, water saturated soils to lose their strength and stiffness, making them flow like a liquid.  As a result, the soil's structure weakens, which can lead to ground subsidence, tilting or sinking of buildings, and other ground failures.

In liquefaction-prone areas, loose, sandy soils or silty soils are most susceptible.  The water between soil particles in these types of soils increases pressure under seismic stress, pushing the particles apart, which leads to a temporary loss of stability.  Liquefaction can have serious implications for infrastructure, as buildings, bridges, and roads built on such soils may suffer severe damage or even collapse if the ground liquefies during an earthquake.