LIQUEFACTION Definition / Introduction: Liquefaction in geology refers to a process in which saturated, unconsolidated sediments (like sand or silt) temporarily lose their strength and stiffness in response to an applied stress—usually caused by an earthquake or sudden loading. When this happens, the ground behaves like a liquid rather than a solid, which can lead to severe ground failure and damage to structures. CONDITIONS FOR LIQUEFACTION: 1. Loose granular soil: Commonly sands and silts. 2.