Could people and vehicles that have mysteriously vanished in the desert have been swallowed up by shifting sands?
Dutch scientists believe their research, showing how very fine, aerated sand can turn into dry quicksand capable of sucking in objects, could offer a possible explanation for puzzling disappearances in the desert.
"The simple fact that we can create a state of sand which does not support weight at all in the laboratory ... means that it could also exist in the real world," said Devaraj van der Meer, of the University of Twente in the Netherlands. "In this sense it could explain the disappearance of people in the desert."
In a study reported in the journal Nature, Van der Meer and his colleagues blew an air stream through very fine sand and allowed it to settle into a unpacked state in the laboratory. When they placed a bowl on top of the sand, it was engulfed.
The same condition, a type of dry quicksand, could evolve in nature from the sedimentation of very fine sand after it has been blown into the air. If it was large enough, it could be dangerous to humans, according to the scientists.
"Indeed, reports that travelers and whole vehicles have been swallowed instantly may even turn out to be credible in the light of our results," the scientists said in the journal.