An Aeolian Grainflow Model for Martian Recurring Slope Lineae.

Icarus

U.S. Geological Survey, Astrogeology Science Center, 2255 N. Gemini Dr., Flagstaff, AZ 86001, USA.

Published: June 2020

Recurring Slope Lineae (RSL) on Mars have been enigmatic since their discovery; their behavior resembles a seeping liquid but sources of water remain puzzling. This work demonstrates that the properties of RSL are consistent with observed behaviors of Martian and terrestrial aeolian processes. Specifically, RSL are well-explained as flows of sand that remove a thin coating of dust. Observed RSL properties are supportive of or consistent with this model, which requires no liquid water or other exotic processes, but rather indicates seasonal aeolian behavior. These settings and behaviors resemble features observed by rovers and also explain the occurrence of many slope lineae on Mars that do not meet the strict definition of RSL. This indicates that RSL can be explained simply as aeolian features. Other processes may add complexities just as they could modify the behavior of any sand dune.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8243843PMC
http://dx.doi.org/10.1016/j.icarus.2020.113681DOI Listing

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