Researchers Uncover 'Secrets' of African Sand Dune
2024-03-10
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1Researchers have used radar and other technologies to study a large "star" sand dune in eastern Morocco.
2The team said it was able to capture detailed data on how these dunes form and develop.
3A star dune is named after its shape because it can look like a star when seen from above.
4These structures are very large and have a hill, or peak, at the top.
5They have large masses, called arms, spreading out from the peak.
6Star dunes are shaped by wind and other conditions in the environment.
7Star dunes are common in deserts and can be found in Africa, the Middle East, China and North America.
8But scientists say, although there are a lot of star dunes, the formations have not been studied very much so far.
9The new study - believed to be the first of its kind - was led by two British researchers.
10It examines a large star dune in the Sahara Desert's Erg Chebbi sand sea in Morocco.
11The research results recently appeared in the publication Scientific Reports.
12The scientists said the star dune rises 100 meters above surrounding dunes and is 700 meters wide.
13The structure contains an estimated five-and-a-half metric tons of sand.
14The researchers used radar that can "see" underground to look at different elements within the star dune.
15The science instruments that were used are designed to map all layers within the dunes.
16They also used a method called luminescence dating to study the age of the dune.
17This method uses minerals in the sand to estimate when they last received sunlight in an attempt to guess the age of the dune.
18Geoff Duller is a professor of geography and earth sciences at Britain's Aberystwyth University.
19He said in a statement the new technology had finally made it possible to study these large dunes.
20"It's only because of new technology that we can start to uncover their secrets," Duller said.
21The researchers estimated the oldest parts of the base of the star dune are about 13,000 years old.
22And the dune is moving across the desert at a rate of about 50 centimeters a year.
23The team noted the star dune experienced the most growth during the past 1,000 years.
24Star dunes make up just 10 percent of all dunes in Earth's deserts.
25They have also been observed on Mars and on Saturn's moon Titan.
26Earth's largest star dunes are found in western China's Badain Jaran desert.
27Star dunes also are found in places including the Namib Sand Sea in Namibia, large sand seas in Algeria and Rub' al Khali in Saudi Arabia.
28In North America, Great Sand Dunes National Park in Colorado contains a series of them.
29"I first encountered star dunes in Namibia 20 years ago," Duller told Reuters news agency.
30He added that he still has clear memories of being surprised at the size and beauty of the first sand dunes he saw.
31"I have a vivid memory of the long climb to the top, struggling up very loose sand in the heat of the day."
32I'm Bryan Lynn.
1Researchers have used radar and other technologies to study a large "star" sand dune in eastern Morocco. The team said it was able to capture detailed data on how these dunes form and develop. 2A star dune is named after its shape because it can look like a star when seen from above. These structures are very large and have a hill, or peak, at the top. They have large masses, called arms, spreading out from the peak. Star dunes are shaped by wind and other conditions in the environment. 3Star dunes are common in deserts and can be found in Africa, the Middle East, China and North America. But scientists say, although there are a lot of star dunes, the formations have not been studied very much so far. 4The new study - believed to be the first of its kind - was led by two British researchers. It examines a large star dune in the Sahara Desert's Erg Chebbi sand sea in Morocco. The research results recently appeared in the publication Scientific Reports. 5The scientists said the star dune rises 100 meters above surrounding dunes and is 700 meters wide. The structure contains an estimated five-and-a-half metric tons of sand. 6The researchers used radar that can "see" underground to look at different elements within the star dune. The science instruments that were used are designed to map all layers within the dunes. They also used a method called luminescence dating to study the age of the dune. This method uses minerals in the sand to estimate when they last received sunlight in an attempt to guess the age of the dune. 7Geoff Duller is a professor of geography and earth sciences at Britain's Aberystwyth University. He said in a statement the new technology had finally made it possible to study these large dunes. "It's only because of new technology that we can start to uncover their secrets," Duller said. 8The researchers estimated the oldest parts of the base of the star dune are about 13,000 years old. And the dune is moving across the desert at a rate of about 50 centimeters a year. The team noted the star dune experienced the most growth during the past 1,000 years. 9Star dunes make up just 10 percent of all dunes in Earth's deserts. They have also been observed on Mars and on Saturn's moon Titan. 10Earth's largest star dunes are found in western China's Badain Jaran desert. Star dunes also are found in places including the Namib Sand Sea in Namibia, large sand seas in Algeria and Rub' al Khali in Saudi Arabia. In North America, Great Sand Dunes National Park in Colorado contains a series of them. 11"I first encountered star dunes in Namibia 20 years ago," Duller told Reuters news agency. He added that he still has clear memories of being surprised at the size and beauty of the first sand dunes he saw. "I have a vivid memory of the long climb to the top, struggling up very loose sand in the heat of the day." 12I'm Bryan Lynn. 13Reuters, Aberystwyth University and Scientific Reports reported on this story. Bryan Lynn adapted the reports for VOA Learning English. 14_____________________________________________ 15Words in This Story 16dune - n. a hill of sand in a desert 17luminescence - n. the giving out of light by a substance 18vivid - adj. clear or strong