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How Common is Quicksand Really, and How Would I Get Out Of It?

A practical guide to a classic movie peril

While “how to escape from quicksand” might sound like something that only applies to Indiana Jones, the stuff is actually more common than you might think.

It’s true: Just because you don’t think you pass a quicksand pit on your way to work doesn’t mean that it’s not there. It occurs on every continent outside of Antarctica, and all it requires to form is some clay, water and sand. So… yeah, it could happen to you, too.

“Quicksand is very common. It can be found most often near the estuary of a river that happens to be transporting clay,” says Daniel Bonn, a professor of physics at the University of Amsterdam. Now, if you’ve forgotten what an estuary is, that’s where a river meets the sea and where freshwater meets saltwater. And while quicksand can exist without salt, it often contains that as well, which makes it even more hazardous. (And if you’re wondering why a physics professor knows so much about quicksand, that’s because Bonn studies soft matter, i.e., items that aren’t quite solid and aren’t quite liquid, which quicksand is a prime example of.)

It’s because of this unusual consistency that quicksand is so dangerous: It’s a substance that changes its viscosity when force is applied. So simply walking on quicksand can liquify it, and if you struggle to try to get out, that will liquify it even more, making you sink deeper. See, when you’re stepping on it, you’re pushing the sand down and the clay and water rise up, trapping your foot. And if there’s salt in there, Bonn explains that it’s, “yet another destabilizing factor.”

The good news, though, is that you can’t really sink all the way down in quicksand. “Quicksand is about twice as dense as you and me,” explains Bonn. “Because we’re basically bags of water, our buoyancy will only allow us to sink about half way.” In other words, unless you decide to dive head-first into quicksand, it can’t really kill you — although if you get stuck in it, you could die of starvation, exposure, hypothermia, or from a hungry nearby crocodile.

Bonn adds that though reports do exist of people drowning in quicksand, it’s widely believed that this occurred because people got stuck while the tide was out, and when it returned, they drowned, “Not in quicksand, but I don’t think you care at that point,” Bonn says.

The big question, then — especially if the tide’s coming in — is, if you find yourself sunk deep in quicksand, is there a way to get out? The answer is yes… but it isn’t easy. While you may think you can just grab onto a rope (or, y’know, a big snake — oh God Indiana Jones and the Crystal Skull why were you SO FUCKING AWFUL) and pull yourself out, this won’t work. In fact, if you’re with a buddy and you fall in quicksand, the last thing you should do is grab his hand to pull yourself out, as you’ll likely just end up pulling him in, too. Bonn points to the example of when you get a boot stuck in mud — if you just pull your foot up, your boot will remain standing there, as it takes quite a bit of force to get it out. With quicksand, the amount of force required to get you out would be roughly the same force it takes to lift a small car off the ground.

The trick — just like with your boot in the mud — is to wiggle. Bonn says, “You have to create some space between your leg and the quicksand.” The way to do that is to wiggle one leg side to side, then let the water fill in that space. Next, you slowly and calmly wiggle your leg more and step upwards. Eventually, you’ll get one leg out, and you’ll continue by working out the next leg until you can crawl your way out of the mud. If you don’t believe this is possible, here’s a video of Bear Grylls doing it:

And if you’re thinking, “Of course Bear Grylls can do it, but my fat ass can’t,” just remember that fat is more buoyant than muscle, so you may actually have less of a distance to go than he did.

And you probably won’t have to drink your own piss, either.