Using radar scans and analysis of sand grains buried deep inside the star dune, scientists mapped the mound’s internal structure. “It’s moving about half a meter per year,” demonstrating that star dunes are about as active as most other dunes, Duller told CNN. A mystery solvedThe new findings also addressed a longstanding mystery for geologists: Where is all the ancient evidence of star dunes? Star dunes are so big; perhaps eroded parts of their preserved structures were previously identified as standalone remnants of other types of dunes, the study authors reported. “The fact that star dunes have not been identified very much in the stratigraphic record may partly be because many geologists were not very much aware of star dunes and only knew about longitudinal dunes and barchans (crescent-shaped dunes),” Goudie said.

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Persons: ” Andrew Goudie, Goudie, ”, Geoff, “, Lala Lallia, Charles Bristow, ” Bristow, Chebbi, Charlie Bristow, Bristow, ” Goudie, ” Mindy Weisberger Organizations: CNN, University of Oxford, Aberystwyth University, sedimentology, Birkbeck College, University of London, University of London's Birkbeck, Google, Scientific Locations: Erg Chebbi, Morocco, United Kingdom, Wales, Aberystwyth, Scotland