Quicksand is a dangerous phenomenon that occurs when loose sand or other granular material becomes saturated with water, causing it to become unstable and collapse. It can be found in many parts of the world, often in areas with sandy soil and high water tables. Quicksand can be
From Wikipedia
Quicksand, also known as sinking sand, is a colloid consisting of fine granular material and water. It forms in saturated loose sand when the sand is suddenly agitated. When water in the sand cannot escape, it creates a liquefied soil that loses strength and cannot support weight. Quicksand can form in standing water or in upward flowing water. In the case of upward-flowing water, forces oppose the force of gravity and suspend the soil particle.