Results 11 to 20 of about 32,835 (209)
“Barchan” dunes in the lab [PDF]
Comptes Rendus. Mécanique, 2002 We demonstrate the feasibility of studying dunes in a laboratory experiment. It is shown that an initial sand pile, under a wind flow carrying sand, flattens and gets a shape recalling barchan dunes. An evolution law is proposed for the profile and the summit of the dune. The dune dynamics is shown to be shape invariant.
Dauchot, Olivier +3 more
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On the crescentic shape of barchan dunes [PDF]
The European Physical Journal B - Condensed Matter, 2004 Aeolian sand dunes originate from wind flow and sand bed interactions. According to wind properties and sand availability, they can adopt different shapes, ranging from huge motion-less star dunes to small and mobile barchan dunes. The latter are crescentic and emerge under a unidirectional wind, with a low sand supply.
P. Hersen, Hersen, P.
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EPJ Web of Conferences, 2017 We show that the orientation and morphology of bedforms occurring on top of Pluto’s smooth ice coats are consistent with an aeolian origin under conditions of unidirectional flow.
Parteli Eric J. R., Pöschel Thorsten
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DETECTION OF BARCHAN DUNES IN HIGH RESOLUTION SATELLITE IMAGES [PDF]
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2016 Barchan dunes are the fastest moving sand dunes in the desert. We developed a process to detect barchans dunes on High resolution satellite images. It consisted of three steps, we first enhanced the image using histogram equalization and noise reduction ...
M. A. Azzaoui +4 more
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Birth of a subaqueous barchan dune [PDF]
Physical Review E, 2017 Barchan dunes are crescentic shape dunes with horns pointing downstream. The present paper reports the formation of subaqueous barchan dunes from initially conical heaps in a rectangular channel. Because the most unique feature of a barchan dune is its horns, we associate the timescale for the appearance of horns to the formation of a barchan dune.
Zambrano, Carlos Azael Alvarez +1 more
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The dune size distribution and scaling relations of barchan dune fields [PDF]
Granular Matter, 2008 6 pages, 4 figures.
Durán, Orencio +3 more
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Corridors of barchan dunes: Stability and size selection [PDF]
Physical Review E, 2004 Barchans are crescentic dunes propagating on a solid ground. They form dune fields in the shape of elongated corridors in which the size and spacing between dunes are rather well selected. We show that even very realistic models for solitary dunes do not reproduce these corridors. Instead, two instabilities take place.
Hersen, Pascal +5 more
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When Barchan Dunes Move Over Craters
Geophysical Research LettersAbstract We investigate the possible outcomes of a subaqueous barchan moving over a crater‐like depression in the bed. For that, we carried out experiments where we varied the dune size, crater and grain diameters, and flow velocities. We found that subaqueous barchans can be blocked, destroyed, or pass over craters, with transitional
Paulo Vitor Ribeiro Plácido +3 more
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Resultant Force on Grains of a Real Sand Dune: How to Measure It?
Geophysical Research LettersBarchan dunes usually appear under the action of one‐directional fluid flows, being found on Earth, Mars, and other celestial bodies; however, although ubiquitous in nature, understanding dune dynamics at the grain scale is challenging due to the vast ...
R. F. Miotto +4 more
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Journal of Geophysical Research: Machine Learning and ComputationThe study of planetary surface processes has traditionally relied on the manual interpretation of spacecraft images. While manual image analysis methods are robust and well‐established, they become impractical when the volume of available data is large ...
Yasmin Hayat, Lior Rubanenko
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