Dry quicksand is loose

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class o ...

whose

bulk density Bulk density, also called apparent density or volumetric density, is a property of powders, granules, and other "divided" solids, especially used in reference to mineral components (soil, gravel), chemical substances, (pharmaceutical) ingredient ...

is reduced by blowing air through it and which yields easily to weight or pressure. It acts similarly to normal

quicksand Quicksand 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 liquefied soil that los ...

, but it does not contain any water and does not operate on the same principle. Dry quicksand is an example of a

granular material A granular material is a conglomeration of discrete solid, macroscopic particles characterized by a loss of energy whenever the particles interact (the most common example would be friction when grains collide). The constituents that compose gra ...

. Historically, the existence of dry quicksand was doubted, and the reports of humans and complete caravans being lost in dry quicksand were considered to be

folklore Folklore is shared by a particular group of people; it encompasses the traditions common to that culture, subculture or group. This includes oral traditions such as tales, legends, proverbs and jokes. They include material culture, ranging ...

. In 2004, it was created in the laboratory, but it is still not clear what its actual prevalence in nature is.

Scientific research

Writing in ''

Nature Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are ...

'',

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

Detlef Lohse and coworkers of

University of Twente The University of Twente (Dutch: ''Universiteit Twente''; , abbr. ) is a public technical university located in Enschede, Netherlands. The university has been placed in the top 170 universities in the world by multiple central ranking tables. I ...

in Enschede,

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

allowed

air The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing f ...

to flow through very fine

(typical grain diameter was about 40

micrometers The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

) in a container with a perforated base. They then turned the air stream off before the start of the experiment and allowed the sand to settle: the packing fraction of this sand was only 41% (compared to 55–60% for untreated sand).. Lohse found that a weighted

table tennis Table tennis, also known as ping-pong and whiff-whaff, is a sport in which two or four players hit a lightweight ball, also known as the ping-pong ball, back and forth across a table using small solid rackets. It takes place on a hard table div ...

ball (radius 2 cm, mass 133 g), when released from just above the surface of the sand, would sink to about five diameters. Lohse also observed a "straight jet of sand hootingviolently into the air after about 100 ms". Objects are known to make a splash when they hit sand, but this type of jet had never been described before. Lohse concluded that :In

nature Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are ...

, dry quicksands may evolve from the

sedimentation Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the ...

of very fine sand after it has been blown into the air and, if large enough, might be a threat to

humans Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

. Indeed, reports that travellers and whole

vehicle A vehicle (from la, vehiculum) is a machine that transports people or cargo. Vehicles include wagons, bicycles, motor vehicles (motorcycles, cars, trucks, buses, mobility scooters for disabled people), railed vehicles (trains, trams), ...

s have been swallowed instantly may even turn out to be credible in the light of our results. During the planning of the Project Apollo moon missions, dry quicksand on the moon was considered as a potential danger to the missions. The successful landings of the unmanned Surveyor probes a few years earlier and their observations of a solid, rocky surface largely discounted this possibility, however. The large plates at the end of legs of the Apollo Lunar Module were designed to reduce this danger, but the astronauts did not encounter dry quicksand.

In popular culture

In ''

Indiana Jones and the Kingdom of the Crystal Skull ''Indiana Jones and the Kingdom of the Crystal Skull'' is a 2008 American action-adventure film directed by Steven Spielberg and the fourth installment in the ''Indiana Jones'' series. Released and taking place 19 years after the previous ...

'' Jones and Marion end up stuck in a dry sandpit. In '' Miss Fisher and the Crypt of Tears'', Phryne Fisher begins to sink in the Palestinian desert and calls out that she is sinking in quicksand. With no water nearby, it is likely meant to be dry quicksand. In ''

Lawrence of Arabia Thomas Edward Lawrence (16 August 1888 – 19 May 1935) was a British archaeologist, army officer, diplomat, and writer who became renowned for his role in the Arab Revolt (1916–1918) and the Sinai and Palestine Campaign (1915–191 ...

'',

T. E. Lawrence Thomas Edward Lawrence (16 August 1888 – 19 May 1935) was a British archaeologist, army officer, diplomat, and writer who became renowned for his role in the Arab Revolt (1916–1918) and the Sinai and Palestine Campaign (1915–1918 ...

's servant Daud dies when falling into quicksand in the desert. In that scene, there is no evidence of water. In ''

The Princess Bride The Princess Bride may refer to: * ''The Princess Bride'' (novel), 1973 fantasy romance novel by American writer William Goldman William Goldman (August 12, 1931 – November 16, 2018) was an American novelist, playwright, and screenwriter. He ...

'', Buttercup falls into dry quicksand, and Westley jumps in to save her. In '' Hotel del Lunas episode 3, Jang Man Wol falls into dry quicksand. In 1999's '' The Mummy'' Rick, Ardeth (Medji), and Captain Winston Havelock crash their plane in the desert and the Captain dies and sinks along with the plane into dry quicksand.

References

External links

Pictures of the quicksand experiment by Lohse et al.

{{Natural disasters Sediments Geological hazards Granularity of materials Soil mechanics ru:Зыбучий песок

Scientific research

In popular culture

See also

References

External links