Dark slope streak

Slope streaks in Acheron Fossae in 2010
Dark slope streaks in Arabia Terra as seen by Mars Orbital Camera (MOC) on Mars Global Surveyor spacecraft. The darkest streaks are only about 10% darker than their surroundings. The greater apparent contrast in the image is due to contrast enhancement[1] Image is 1.65 km (1 mi) across. North is at bottom.

Dark slope streaks are narrow, avalanche-like features common on dust-covered slopes in the equatorial regions of Mars.[2] They form in relatively steep terrain, such as along escarpments and crater walls.[3] [4] Although first recognized in Viking Orbiter images from the late 1970s,[5][6] dark slope streaks were not studied in detail until higher-resolution images from the Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO) spacecraft became available in the late 1990s and 2000s.[1][7]

The physical process that produces dark slope streaks is still uncertain. They are most likely caused by the mass movement of loose, fine-grained material on oversteepened slopes (i.e., dust avalanches).[1][8][9] The avalanching disturbs and removes a bright surface layer of dust to expose a darker substrate.[10] The role that water and other volatiles plays, if any, in streak formation is still debated.[11] Slope streaks are particularly intriguing because they are one of the few geological phenomena that can be observed occurring on Mars in the present day.[12][13][14] [15][16]

  1. ^ a b c Sullivan, R. et al. (2001). Mass Movement Slope Streaks Imaged by the Mars Orbiter Camera. J. Geophys. Res., 106(E10), 23,607–23,633.
  2. ^ Chuang, F.C.; Beyer, R.A.; Bridges, N.T. (2010). Modification of Martian Slope Streaks by Eolian Processes. Icarus, 205 154–164.
  3. ^ https://www.uahirise.org/ESP_040386_1915
  4. ^ Schorghofer, N.; Aharonson, O.; Khatiwala, S. (2002). Slope Streaks on Mars: Correlations with Surface Properties and the Potential Role of Water. Geophys. Res. Lett., 29(23), 2126, doi:10.1029/2002GL015889.
  5. ^ Morris, E.C. (1982). Aureole Deposits of the Martian Volcano Olympus Mons. J. Geophys. Res., 87(B2), 1164–1178.
  6. ^ Ferguson, H.M.; Lucchitta, B.K. (1984). Dark Streaks on Talus Slopes, Mars in Reports of the Planetary Geology Program 1983, NASA Tech. Memo., TM-86246, pp. 188–190. https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19840015363_1984015363.pdf.
  7. ^ Chuang, F.C. et al. (2007). HiRISE Observations of Slope Streaks on Mars. Geophys. Res. Lett., 34 L20204, doi:10.1029/2007GL031111.
  8. ^ Sullivan, R.; Daubar, I.; Fenton, L.; Malin, M.; Veverka, J. (1999). Mass-Movement Considerations for Dark Slope Streaks Imaged by the Mars Orbiter Camera. 30th Lunar and Planetary Science Conference, Abstract #1809. http://www.lpi.usra.edu/meetings/LPSC99/pdf/1809.pdf.
  9. ^ Barlow, 2008, p. 141.
  10. ^ "Read, Publish, Review". AGU. Retrieved 2022-09-30.
  11. ^ Webster, Guy; Brown, Dwayne (December 10, 2013). "NASA Mars Spacecraft Reveals a More Dynamic Red Planet". NASA. Retrieved December 10, 2013.
  12. ^ Kreslavsky, M.A.; Head, J.W. (2009). Slope Streaks on Mars: A New "Wet" Mechanism. Icarus, 201 517–527.
  13. ^ Aharonson, O.; Schorghofer, N.; Gerstell, M.F. (2003). Slope Streak Formation and Dust Deposition Rates on Mars. J. Geophys. Res., 108(E12), 5138, doi:10.1029/2003JE002123.
  14. ^ Dundas, C. 2018. HIRISE OBSERVATIONS OF NEW MARTIAN SLOPE STREAKS. 49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083). 2026.pdf
  15. ^ Junior, C. and T. Statella. 2023. Monitoring martian slope streaks in the northeast of Lysus sulci. Icarus. 406: 115737.
  16. ^ Bhardwaj, A., et al. 2018. Are Slope Streaks Indicative of Global-Scale Aqueous Processes on Contemporary Mars? Reviews of Geophysics: Volume 57, Issue 1 p. 48-77