Is there really such a thing as quicksand and if so, what do I do if I fall in some of it?

Answer 1

Yes quicksand exists, but it is much rarer than Hollywood or the old Tarzan movies would have you think.

The sand is suspened in water and looks solid or gel like, ut it is actually a very thick liquid (salt can make it thicker). What causes the problem is when it is disturbed and the water is squeezed out of the sand solution, then the person can sink in it. Movement is hard because they have to move against the near solid sand and can only do so by pushing the water out. Since the human body is mostly water and we all have some fat you can do a back float on quicksand and survive exposure. Movement will be slow because of the force of the sand. A person can drown if the quicksand pit is over their head, but if they don't panic and back float then they can survive.

The property that gives quicksand its nature is called viscosity; a fluid with a high viscosity is thick and hard to flow. Old engine oil gets like that. Quicksand has a very high viscosity because the sand is suspended not dissolved in the solution. To move you have to squeeze the water out of the sand to give yourself a medium that you can move through, and then you have to move around the solid sand. Hence the quote: “ to remove a foot from quicksand at a speed of one centimeter per second would require the same amount of force as "that needed to lift a medium-sized car.”

"Quicksand is a colloid hydrogel consisting of fine granular matter (such as sand or silt), clay, and salt water. The origin of the name refers to "quick" in the older meaning of "alive" rather than "fast," and is thus similar to the origin of the term quicksilver for mercury.

Quicksand is a non-Newtonian fluid: when undisturbed it often appears to be solid ("gel" form), but a minor (less than 1%) change in the stress on the quicksand will cause a sudden decrease in its viscosity ("sol" form). After the initial perturbation—such as a person attempting to walk on it—the water and sand in the quicksand separate and dense regions of sand sediment form; it is because of the formation of these high volume fraction regions that the viscosity of the quicksand seems to suddenly increase. In order to move within the quicksand, a person or object must apply sufficient pressure on the compacted sand to re-introduce enough water to liquefy it. The forces required to do this are quite large: to remove a foot from quicksand at a speed of one centimeter per second would require the same amount of force as "that needed to lift a medium-sized car." [1]

It was commonly believed that the behavior of quicksand was due solely to saturated or supersaturated suspensions of granules in water. Pressure from underground sources of water would separate and suspend the granular particles, reducing the friction between them. As of September 2005, it has been shown that it is the presence of salt that is largely responsible.[1] The stability of the colloidal quicksand is compromised by the presence of salt, increasing the likelihood of sand flocculation and the formation of the high viscosity regions of sediment responsible for quicksand's "trapping" power.

Quicksand can be found inland (on riverbanks, near lakes, or in marshes) or near the coast.

One region notorious for its quicksands is Morecambe Bay, England. As the bay is very broad and shallow, a person trapped by the quicksand would be exposed to the danger of the returning tide, which can come in rapidly."

Answer 2

its real and if u fall in it, float ive always heard.