slave boss is doing a backstroke (breaststroke?) through quicksand
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Here is the article on quicksand from https://en.wikipedia.org/wiki/Quicksand
{{Short description|Mixture of sand, silt or clay with water, which creates a
liquefied soil when agitated}}
{{About|the geological feature}}
{{More citations needed|date=April 2022}}
[[File:Quicksand warning.jpg|thumb|right|Quicksand and a warning sign about it
at a gravel quarry in England]]
[[File:Quicksand (4596511338).jpg|thumb|Quicksand on the [[River
Thames|Thames]]]]
'''Quicksand''' (also known as '''sinking sand''') is a [[colloid]] consisting
of fine [[granular material]] (such as [[sand]], [[silt]] or [[clay]]) and
[[water]]. It forms in saturated loose sand when the sand is suddenly agitated.
When water in the sand cannot escape, it creates a [[Liquefaction|liquefied]]
soil that loses strength and cannot support weight. Quicksand can form in
standing water or in upward flowing water (as from an [[Artesian
aquifer|artesian spring]]). In the case of upward-flowing water, [[effective
stress|forces]] oppose the force of gravity and suspend the soil particle.
The cushioning of water gives quicksand, and other liquefied sediments, a
spongy, fluid-like texture. In accordance with [[Archimedes' principle]],
objects in liquefied sand sink to the level at which the weight of the object
is equal to the weight of the displaced soil/water mix and the submerged object
floats due to its buoyancy.
[[Soil liquefaction]] may occur in partially saturated soil when it is shaken
by an [[earthquake]] or similar forces. The movement combined with an increase
in [[pore pressure]] (of groundwater) leads to the loss of particle [[Cohesion
(chemistry)|cohesion]], causing buildings or other objects on that surface to
sink.
== Properties ==
[[File:Stuck in Quicksand (13944309974).jpg|thumb|A group of hikers
encountering quicksand on the banks of the [[Paria River]], Utah]]
[[File:Quicksandwarning.JPG|thumb|Quicksand warning sign near [[Lower King,
Western Australia|Lower King]] Bridge, Western Australia]]
Quicksand is a [[shear thinning]] [[non-Newtonian fluid]]: when undisturbed, it
often appears to be [[phase (matter)|solid]] ("[[gel]]" form), but a less than
1% change in the [[stress (physics)|stress]] on the quicksand will cause a
sudden decrease in its [[viscosity]] ("[[sol (colloid)|sol]]" form). After an
initial disturbance—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 decrease suddenly. Someone stepping on it
will start to sink. To move within the quicksand, a person or object must apply
sufficient [[pressure]] on the compacted sand to re-introduce enough water to
[[liquefaction|liquefy]] it. The [[force]]s required to do this are quite
large: to remove a foot from quicksand at a speed of 1 cm/s would require
the same amount of force as that needed to lift a car.<ref
name="Bonn">Khaldoun, A., E. Eiser, G. H. Wegdam, and Daniel Bonn. 2005.
[http://www.nature.com/nature/journal/v437/n7059/full/437635a.html "Rheology:
Liquefaction of quicksand under stress."] ''Nature'' 437 (29 Sept.): 635.
{{doi|10.1038/437635a}}</ref>
It is impossible for a human to sink entirely into quicksand,<ref
name=":0">{{Cite
web|url=http://thescienceexplorer.com/nature/will-quicksand-really-kill-you|title=Will
Quicksand Really Kill You?|website=The Science
Explorer|language=en|access-date=2020-04-08}}</ref> due to the higher
[[density]] of the fluid. Quicksand has a density of about 2 grams per cubic
centimeter, whereas the density of the human body is only about 1 gram per
cubic centimeter. At that level of density, sinking beyond about waist height
in quicksand is impossible. Even objects with a higher density than quicksand
will float on it if stationary. Aluminium, for example, has a density of about
2.7 grams per cubic centimeter, but a piece of aluminium will float on top of
quicksand until motion causes the sand to liquefy.<ref name=Bakalar>{{cite web
|url=https://www.nationalgeographic.com/science/article/quicksand-science-why-it-traps-how-to-escape/
|archive-url=https://web.archive.org/web/20210221081902/https://www.nationalgeographic.com/science/article/quicksand-science-why-it-traps-how-to-escape
|url-status=dead |archive-date=February 21, 2021 |title=Quicksand Science: Why
It Traps, How to Escape |first1=Nicholas |last1=Bakalar |publisher=[[National
Geographic News]] |date=September 28, 2005 |access-date=October 9, 2011}}</ref>
Continued or panicked movement, however, may cause a person to sink further in
the quicksand.<ref>{{cite news |last1=Gleeson |first1=Bill |title=Sinking sand
is notorious near Crosby - here's what you need to know
|url=https://www.liverpoolecho.co.uk/news/liverpool-news/sinking-sand-notorious-near-crosby-11794759
|work=Liverpool Echo |date=24 August 2016 |language=en}}</ref> Since this
increasingly impairs movement, it can lead to a situation where other factors
such as exposure (i.e., [[heat stroke|sun stroke]], [[dehydration]] and
[[hypothermia]]), [[drowning]] in a rising [[tide]] or [[animal
attack|attacks]] by [[Predation|predatory]] or otherwise aggressive animals may
harm a trapped person should they not be rescued.<ref>[[Discovery Channel]].
''[[MythBusters]]''. Season 2. [[MythBusters (2004 season)#Episode 19 .E2.80.93
.22Killer Quicksand.22|"Killer Quicksand."]] October 20, 2004.</ref>
Quicksand may be escaped by slow movement of the legs in order to increase
viscosity of the fluid, and rotation of the body so as to float in the [[supine
position]] (lying horizontally with the face and torso facing up).<ref
name=Bakalar/>
==In popular culture==
Quicksand is a [[Trope (literature)|trope]] of [[adventure fiction]],
particularly in film, where it is typically and unrealistically depicted with a
suction effect that causes anyone or anything that walks into it to sink until
fully submerged and risk drowning. This has led to the [[List of common
misconceptions|common misconception]] that humans can be completely immersed
and drown in quicksand, which is impossible.<ref>{{Cite
web|url=https://www.abc.net.au/science/articles/2005/09/29/1471116.htm|title=Quicksand
myth exposed|first=Patricia|last= Reaney|publisher=Reuters|date=29 September
2005|website=www.abc.net.au|language=en-AU|access-date=2020-04-08}}</ref>
According to a 2010 article by ''[[Slate (magazine)|Slate]]'', this gimmick had
its heyday in the 1960s, when almost 3% of all films showed characters sinking
in clay, mud, or sand.<ref name="Engber 2010">{{cite
news|last=Engber|first=Daniel|title=Terra Infirma: The rise and fall of
quicksand.|url=http://www.slate.com/id/2264312/|access-date=23 August
2010|newspaper=Slate|date=23 August 2010}}</ref>
== See also ==
* [[Bulldust]]
* [[Dry quicksand]]
* [[Grain entrapment]]
* [[Quick condition]]
* [[Sand boil]]
* [[Sapric]]
* [[Tar pit]]
* [[Thixotropy]]
==References==
{{Reflist}}
==External links==
{{Commons category|Quicksand}}
{{Wikiquote}}
{{Wiktionary|quicksand}}
* [http://science.howstuffworks.com/quicksand.htm How quicksand works] at
[[HowStuffWorks]]
* {{cite news |title=What Is Quicksand?
|url=http://www.sciam.com/article.cfm?id=what-is-quicksand |work=[[Scientific
American]]}}
* [https://www.youtube.com/watch?v=Swdm4j4tpN0 Video showing quicksand in a
sandpit] at [[YouTube]]
{{Authority control}}
[[Category:Geological hazards]]
[[Category:Sand]]
[[Category:Sediments]]
[[Category:Soil mechanics]]
