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A Recipe For Quicksand

Tuesday, October 15, 2013 - 04:00 PM

an upclose shot of a quicksand mud pit, that looks bubbly and thick gray sploshy Head to north central Arkansas to see this eight year old pit used to film quicksand scenes in movies. (Studio 588)

Hey guys – we got your weekend plans all figured out: Build your own quicksand pit!

What gives quicksand its wriggle-worthy properties? Its non-Newtonian nature, of course (you didn’t see that coming). The properties associated with being one of those wacky fluids is their ability to change viscosity based on the rate and force of applied stress. Quicksand is the echt example but ketchup, gak, and bogs are all non-Newtonian. Thankfully, you don’t have to be Newton to build your own pit. You just need to know Fred.

We found Fred through Dan Engber, the journalist who got us all thinking about the goopy stuff for our Quicksaaaand! podcast. Dan ran into Fred while researching the quicksand fetish community; Fred is the managing director of a studio where films featuring quicksand are made (he prefers we don't use his last name). As part of his job, Fred is the guy who re-creates different types of quicksand pits. He told us that depending upon the size, shape, and distribution of particles you use, there are two types "quicksand" you can create, based on the two ways non-Newtonian fluids behave.

Traditional sand-based quicksand is thixotropic. So when undisturbed, it is solid-like, but when suddenly shaken or agitated, it becomes less viscous and more fluid. In laymen’s terms, if you come across one of these pits when you’re furiously running down a jungle trail (away from Sasquatch, obvi), the moment you hit the pit’s surface you disrupt the sand's placid state, making it more liquid-y, less solid-y, and thus able to suck you in.

“Traditional quicksand is sand in a constricted area, with water percolating up through it," says Fred. "What happens is the sand particles are lifted by the pressure underneath, making a cap on top that looks like walkable ground.”

When someone steps on the surface, their body weight displaces the deeper water, causing it to rise to the surface.

Another funky behavior of non-Newtonian fluids can be seen in game shows, where contestants run across pools of cornstarch and water. No, they aren't walking on water, rather, they are banking on the other way non-Newtonian fluids can behave. Known as dilatancy, this property is defined by a fluid's ability to harden under stress. Sadly, or perhaps fortunately, dilatancy pits are only found on game shows, not out in nature (but if you do find yourself on a game show, and you want to get in, then you need to inch in slowly).

Natural quicksand pits come in many different flavors, from sand to clay or peat. Keep in mind, says Fred, “Sand is the most dangerous."

"You may only be knee-deep, but once the sand locks up, you become trapped and exposed to the elements," he explains.

Want to make your own pits? Here are some recipes to sink by.

Some safety notes: 

*If you get sucked into sandy quicksand, once you stop moving, the sand will return to a more solid state, and trap you. So it turns out, the more you wriggle and squirm, the looser the sand will become, allowing space for your body and allowing you to get out. In quicksand prone areas, like Alaska, fire fighters sometimes use a wand (for our purposes, any hose will work) to shoot water or air underneath the trapped body, loosening the sand particles and voila! Freedom!

*Clay is quite slippery when wet, so be sure to have a dry rope nearby to pull your body out.

*To sanitize any of your pits (expect the peat one to grow its own ecosystem of bugs and bees, says Fred), you can occasionally shock them with chlorine.

*Remember folks, don’t make the pit any deeper than you are tall; Fred keeps his around five feet. 

** OBLIGATORY WARNING!

Hey kids, if you do successfully build a quicksand pit, don't be evil and lure unsuspecting people and animals into it. And don't get yourself stuck with no hope of rescue.

 

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Comments [10]

Henry from Fart.com

Faaaaaaaaaaaaaaaaaaaaaart

Nov. 20 2013 10:58 AM
Briana from Binghamton Ny

I find it interesting that according to this program, right now children's biggest fear is the "Zombie Apocalypse." This make me wonder if this current fear has any correlation to society's obsession with escaping via electronic devises, mind numbing "media," etc... So many of us are consumed by being plugged in electronically, that we are walking around tuned out to the world (and people)around us. I may be stretching a bit but quick sand is a reality while Zombies are not, however the fact that we live in a society of escapism Zombies are a more tangible fear to children than quick sand is.

Nov. 14 2013 01:17 PM
Tom Bleck from Wadsworth Il

I was trapped in sandy quicksand while fishing in a stream in northern Wisconsin It was located on an instide river bank I stepped from the grassy bank onto what I thought was solid sand and sank down to about chest deep in four seconds. I pulled out grabbing the grass and swam up the bank. 20 minutes before I was fishing standing on a hard sand bottom on the opposite shore 20 feet away.

Oct. 29 2013 11:34 PM
Dave Doepner from Salt Lake City, Utah

Quicksand is fairly common in the slot canyons of the Colorado Plateau and I've found myself in ankle, knee or thigh deep on a number of occasions. Sometimes there is enough water, usually from a side channel, to make it very Quick. Most of the time it's the gooey stuff you can play with, cooling your heels when it gets too hot to hike. The next time I'm there I'll be able to use this info to explain to my hiking partners exactly what they are going through. And yes, I'll be sure to add the fetish angle just to see how they respond.

Oct. 22 2013 02:07 PM
Major from WV

Will the clay pit ever dry up?

Oct. 19 2013 12:34 PM
EG Gilbert from Minneapolis, Minnesota

The Beetle Bailey comic 10/19/2013 has Sarge in quicksand.

Oct. 19 2013 10:59 AM
Cory in Rome from Italy

What amazing timing you guys have! I just used the quicksand analogy with a young person this week. When I got no fear response, I wondered if it was the fact that I'm in Italy or if fear of quicksand was a cultural phenomenon of the 60's. When I was a kid in California we were all terrified of quicksand.

Oct. 17 2013 12:03 PM
Stan Rosenbaum from Lexington, KY


Interesting episode, but I think you guys missed one very huge point about Quicksand.

Maybe I am taking the knowledge of myself and my peers for granted, but it seems to me that the 'ominous' characteristics of quicksand have been neutralized by the common knowledge that quicksand really isn't dangerous.

I mean, I would be interested to know if any of the kids the reporters talked to really thought that quicksand was dangerous?

Most people I know [and most well read kids], will probably know that quicksand is denser then water, and that if one doesn't struggle a normal human floats in quicksand and can easily pull themselves out.

I think you guys sort of a missed that big part about quicksand.

Oct. 16 2013 09:11 PM
Sam Lee from London

Brilliant episode. As a kid, I had a fear of accidentally stepping in quicksand (even though I grew up in London). How ridiculous! Then as if to say to prove it could happen, I came across this news reel about a woman who had to be rescued from deep mud:
http://www.independent.co.uk/video/?videoid=2710552573001

Oct. 16 2013 05:37 PM
Jonathan Baker

Loved this episode. So bizarre, but strangely not surprising about all of the fetishes.

Oct. 16 2013 10:22 AM

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