Killer Quicksand

posted: 04/11/12
Read more Read less
As seen in "MythBusters: Killer Quicksand"
Martin Klimek / Getty Images

Finding: BUSTED

Explanation: In old Tarzan movies, the king of the jungle liked to trap his enemies in killer quicksand that could suck them down to a grimy grave. But MythBusters Jamie Hyneman and Adam Savage wondered whether Tarzan's deathtrap was based on shaky science.

In nature, quicksand works by a process called liquefaction, in which water rising from the ground separates sand granules so they can't support any weight. By Hollywood standards, liquefaction translates to terrifying suction power.

To simulate a quicksand quagmire, the MythBusters filled a 2,000-gallon (7,571-liter) tank with ultrafine sand, or sugar sand. They then piped water into the bottom of the tank, allowing it to saturate the sugary silt, reducing the friction between the tiny particles. When Jamie and Adam each stepped into the homemade quicksand tank, they certainly sank down — but only to a point.

Once submerged to their chests, the MythBusters didn't descend any farther, because the quicksand mixture was more dense than their bodies. They were surprisingly buoyant, actually, and the quicksand supported their bodies instead of sucking them downward.

The buoyancy effect busted the killer quicksand myth and discredited Tarzan's silver-screen fighting tactics.

More on