Mystery of Giant Moving Star Dune Revealed: “A Wonder of Nature”

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Experts from a number of universities have now pinpointed the age of a star dune in a remote area of ​​Morocco and revealed details about its formation and how it moves through the desert.

The team, which also included scientists from the University of London, traveled to south-east Morocco to study a 100-metre-high, 700-metre-wide dune in the Erg Chebbi sand sea known as Lala Lallia, which means “the highest sacred site” in Berber. period,” writes The Guardian

Professor Geoff Daller, from the Department of Geography and Geosciences at Aberystwyth, said: “This is extraordinary stuff, one of the natural wonders of the world. From the ground they look like pyramids, but from the air you see the top and the branches radiating from it in three or four directions, which make them look like stars.”

The researchers found that the very base of the dune was 13,000 years old, but were surprised that the upper part of the structure had only formed in the last 1,000 years or so. “She turned out to be surprisingly young,” says Professor Dallaire.

The base continued to grow until about 9,000 years ago. “Then the surface stabilized,” the scientist notes. “We think it was a little wetter than today.” We can see traces of old plant roots, suggesting that the dune was stabilized by vegetation. It seems that this went on for about 8,000 years. Then the climate began to change again, and this star dune began to form.”

Dallaire argues that the dune was formed due to the fact that the wind blows in two opposite directions – from the southwest and northeast, which leads to the accumulation of sand. A steady third wind, which blows from the east, slowly moves the dune westward at a speed of about 50 cm per year.

“This is important when you think about building roads, pipelines or any other infrastructure,” Dallaire said. “These things actually move.”

Luminescence dating techniques have been used to detect the last time minerals in sand were exposed to sunlight to determine their age.

Professor Dallaire said: “We’re not looking at when the sand was formed – that’s millions of years ago – but at when it was deposited. Quartz grains have the property of being a mini rechargeable battery. It can store energy that it receives from natural radioactivity. When we get him back to the lab, we can force him to release this energy. It appears in the form of light. We can measure it and the brightness will tell us when a grain of sand last saw daylight.”

One catch is that they must collect sand grains without exposing them to light. The scientists did this by cutting holes in the dunes and hammering an old piece of drainpipe to collect samples, explains The team, which also included scientists from the University of London, traveled to southeastern Morocco to study a 100-meter-high, 700-meter-wide sand dune. Erg Chebbi sea, known as Lala Lallia, which means “highest sacred point” in the Berber language, writes The Guardian.

“This part is not very high-tech,” notes Dallaire. Laboratory work, which is much more high-tech and sensitive, must be performed under the same conditions as a darkroom.

The same luminescence technique was used to date the remains of what is believed to be the world’s oldest known wooden structure, an arrangement of logs along a river bordering Zambia and Tanzania that predates the advent of modern humans.