QUICKSAND BEACH TV

The sand becomes “quick” when motion, loading, vibration or upward migration of water breaks down the friction that holds the grains in place.

If gently placed on quicksand, even dense materials will rest on the surface.

The volume of water-filled void space is often greater than the volume of grains.

Normal sand is packed together with about 25-30% of void space between the grains, but in quicksand, grains are more loosely packed with 30-70% porosity.

Desert quicksand (with air-filled voids) may occur on the downwind side of dunes, but usually only a couple inches of sinking occurs in these cases, as the air is quickly expelled when the sand compacts under a load or vibration.

Quick conditions may occur on beaches and tidal flats during low tides as the retreating sea leaves behind saturated sand.

The force of shaking during earthquakes may increase groundwater pore pressure and trigger liquefaction of surface sand or silt, causing building foundations to shift.

Natural springs can cause quick conditions to occur in alluvial fans or along riverbanks.

It is a “shear thinning non-Newtonian fluid,” meaning that when undisturbed, the hydrogel looks solid, but just 1% change in stress will cause a sudden decrease in viscosity, or fluidization.

Quicksand is a colloid hydrogel made up of loosely packed granular material that is saturated with water, creating a suspension.

Quicksand in Courthouse Wash at Arches National Park in Utah. After the 1960s, quicksand was used more as a comedic or ironic device, such as in Blazing Saddles and Indiana Jones and the Kingdom of the Crystal Skull.

The peak of quicksand-related films occurred in the 1960s when one out of 33 films (3%) included some sort of a quicksand hazard.Rescued from Quicksand-the story of the rescue of a young woman from quicksand on a beach by monks from a local monastery-lasted 12 minutes. The first film to use quicksand dramatically was made in 1909.Once moving pictures were invented, filmmakers looked for dramatic situations to record, and images of quicksand struggles became popular.But what is quicksand and can you really be swallowed alive by it?

QUICKSAND BEACH TV

Synopsis: From Oscar-winning films like Lawrence of Arabia to TV episodes of Lassie and Tarzan, the hazard of quicksand fascinated viewers of the mid-20th century so much that 3% of films of that time included someone sinking inexorably into the earth. Once free, you can slowly crawl or swim to the edge and roll onto solid ground. Then gradually recline to float on the surface. Wiggle your legs in tiny movements, which will slowly let water in to loosen the compacted sand. The key to getting out is to remain calm. The more you struggle, the more sand will liquefy and sink, and the more trapped you’ll become. Because humans are buoyant, we typically won’t sink below the waist or mid-chest.īut once the sand grains are out of liquid suspension, they too will sink, and compact around your legs, trapping you. Quicksand looks solid, and if you were to place something or even step lightly upon it, it may support you.īut step firmly and the quicksand will liquefy, and you’ll sink. In those places, look out for sand that’s spongy or rippled in appearance, and check suspicious areas with a stick. Quicksand can form on beaches, tidal flats, riverbanks or near springs-anywhere the ground is saturated with water. Normal wet sand is about 25 percent water quicksand is more than 70 percent. It starts by knowing where quicksand forms and what it looks like. What can you do to avoid getting trapped-and to escape if you do? Getting caught in quicksand can be fatal, with victims dying mostly from dehydration, hypothermia or heat exhaustion. Credit: Ralf Schulze from Koblenz, Germany

This sign says “Take care! Quicksand” on the beach of Texel Island in the Netherlands.

Quicksand beach