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Dark slope streak
Surface feature of Mars / From Wikipedia, the free encyclopedia
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] Although first recognized in Viking Orbiter images from the late 1970s,[4][5] 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][6]
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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][7][8] The avalanching disturbs and removes a bright surface layer of dust to expose a darker substrate.[9] The role that water and other volatiles plays, if any, in streak formation is still debated.[10] 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.[11][12][13] [14][15]