Yardangs are common in some regions on Mars, especially in the Medusae Fossae Formation. This formation is found in the Amazonis quadrangle and near the equator.[1] They are formed by the action of wind on sand sized particles; hence they often point in the prevailing direction that the winds were blowing when they were formed.[2][3] Yardangs exhibit very few impact craters, indicating that the surface exposed is relatively young and the process of erosion may be active.[4] The easily eroded nature of the Medusae Fossae Formation suggests that it is composed of weakly cemented particles, and was most likely formed by the deposition of wind-blown dust or volcanic ash. Yardangs are parts of rock that have been sand blasted into long, skinny ridges by bouncing sand particles blowing in the wind.[5][6] Layers are seen in parts of the formation. A resistant caprock on the top of yardangs has been observed in Viking,[7] Mars Global Surveyor,[8] and HiRISE photos.[9] Images from spacecraft show that they have different degrees of hardness probably because of significant variations in the physical properties, composition, particle size, and/or cementation.

Zooming on the yardangs of Mount Sharp with Remote Micro Imager on the Curiosity rover - sol 1994

See also

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References

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  1. ^ SAO/NASA ADS Astronomy Abstract Service: Yardangs on Mars, Journal of Geophysical Research Vol. 84, Issue B14, 30 December 1979. https://doi.org/10.1029/JB084iB14p08147
  2. ^ Yardangs on Mars, ESA Mars Express, 23 Jul 2004
  3. ^ ESA High-resolution image, Yardangs on Mars near Olympus Mons on Mars, image taken by the High Resolution Stereo Camera (HRSC) on board the ESA Mars Express spacecraft.
  4. ^ THEMIS image of Medusae Fossae Formation, ASU, 2002-04-16
  5. ^ a b Yardangs in Arsinoes Chaos University of Arizona HiRISE Operations, 04 January 2015
  6. ^ "HiRISE | Yardangs in Arsinoes Chaos (ESP_039563_1730)".
  7. ^ Scott, David H.; Tanaka, Kenneth L. (1982). "Ignimbrites of Amazonis Planitia Region of Mars". Journal of Geophysical Research. 87: 1179–1190. Bibcode:1982JGR....87.1179S. doi:10.1029/JB087iB02p01179.
  8. ^ Malin, MC; Carr, MH; Danielson, GE; Davies, ME; Hartmann, WK; Ingersoll, AP; James, PB; Masursky, H; et al. (March 1998). "Early views of the martian surface from the Mars Orbiter Camera of Mars Global Surveyor". Science. 279 (5357): 1681–5. Bibcode:1998Sci...279.1681M. doi:10.1126/science.279.5357.1681. PMID 9497280.
  9. ^ Mandt, Kathleen E.; De Silva, Shanaka L.; Zimbelman, James R.; Crown, David A. (2008). "The origin of the Medusae Fossae Formation, Mars: Insights from a synoptic approach". Journal of Geophysical Research. 113: 12011. Bibcode:2008JGRE..11312011M. doi:10.1029/2008JE003076. hdl:10088/7052.