Scientists reveal secrets of mini dunes on Earth and Mars
Scientists from the University of Southampton have discovered how miniature dunes form on Earth and Mars. The research may also help understand similar formations on other planets.
Researchers from the University of Southampton in England, in collaboration with research institutes in France, have unveiled the mechanism behind the formation of miniature dunes on beaches and in deserts. The findings, published in the scientific journal "PNAS," shed new light on the formation of "proto dunes" on Earth and may provide insight into similar structures on Mars and other planets.
They captured the process of dune formation using a laser
"These are the kind of smaller scale sand bedforms that people would see forming before their eyes on the beach before the wind stops or the waves wash them away," explained Professor Jo Nield, who led the research, to the SciTechDaily portal. Previous theories regarding large desert dunes did not explain how these smaller formations arise on damp surfaces, such as beaches or hard, gravelly areas.
An international research team, with members from Southampton, Paris, Oxford, Loughborough, Illinois, and Denver, has captured the formation of these small dunes using high-resolution laser scanning in the Namibian desert. They discovered that sand moving over harder, more consolidated surfaces bounces higher and is more easily transported by the wind. When it lands on a softer, rippled surface, the sand accumulates.
"Proto dunes" are also on Mars
Professor Philippe Claudin from the French National Centre for Scientific Research (CNRS) added that the model can almost perfectly recreate what is seen in the field data. "Interestingly we see similar patterns in arid areas with gravel and coastal areas where there's moisture," he explained. The model enables the team to adjust various parameters, such as the amount of sand and wind strength, to explore different scenarios.
These "proto-dunes" aren't exclusive to Earth. The research team is now investigating dune formation on Mars. Professor Nield highlights their enthusiasm about applying Earth-based findings to the Martian environment to explore the commonalities and distinctions between proto-dunes on the two planets.
