In low spots on the Colorado Plateau where sediment accumulates in the presence of water, pockets of quicksand may form without warning. Especially near lake shores and in creek beds – including along Paria Canyon and around Lake Powell.
Quicksand is formed when sand and clay particles become loosely suspended in water. The fragile jelly-like mixture is stabilized by weak electrical charge differences between the surfaces of the clay particles.
Any salts in the water decrease those stabilizing forces – making the watery structure even weaker. A tiny amount of pressure may cause the quicksand’s viscosity to suddenly drop - by a factor of nearly a million, as the ‘house-of-cards’ collapses.
So, while quicksand may look like an unusually smooth patch of solid sand, when you step on it, the seemingly solid surface instantly gives way. Dense sediment redeposits around your feet and legs, It can can require a huge amount of force to pull free.
Typical quicksand is twice as dense as the human body so, even if you step in a deep patch, you will not sink all the way under – only to around waist level. But while quicksand is not intrinsically life threatening, becoming dehydrated, hypothermic, or overwhelmed by rising water while trapped in it, can be.
If you do become stuck, remain calm. Rock your legs gently back-and-forth, to reliquefy the quicksand around them, until you can pull free. Then, spreading your body as flat as possible, slowly crawl to firmer ground.
This Earth Note was written by Diane Hope and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.
