Granular flows at recurring slope lineae on Mars indicate a limited role for liquid water

  title={Granular flows at recurring slope lineae on Mars indicate a limited role for liquid water},
  author={Colin M. Dundas and Alfred S. McEwen and Matthew Chojnacki and Moses P. Milazzo and Shane Byrne and Jim N. McElwaine and A. C. Urso},
  journal={Nature Geoscience},
Recent liquid water flow on Mars has been proposed based on geomorphological features, such as gullies. Recurring slope lineae — seasonal flows that are darker than their surroundings — are candidate locations for seeping liquid water on Mars today, but their formation mechanism remains unclear. Topographical analysis shows that the terminal slopes of recurring slope lineae match the stopping angle for granular flows of cohesionless sand in active Martian aeolian dunes. In Eos Chasma, linea… 
Geomorphological evidence for a dry dust avalanche origin of slope streaks on Mars
  • C. Dundas
  • Geology, Physics
    Nature Geoscience
  • 2020
Patterns of erosion and deposition by some slope streaks on Mars are consistent with a dry dust avalanche origin, according to an analysis of orbital images before and after new streaks formed.
High‐Resolution Thermal Environment of Recurring Slope Lineae in Palikir Crater, Mars, and Its Implications for Volatiles
A thermophysical model for rough terrain is developed that is capable of processing spatial domains of megapixel size. This computational advance makes it possible to characterize thermal
Changes in Soil Cohesion Due to Water Vapor Exchange: A Proposed Dry‐Flow Trigger Mechanism for Recurring Slope Lineae on Mars
Recurring slope lineae (RSL) are seasonal flows on steep slopes on Mars. Their formation mechanism is unknown, but dry granular flows are a likely explanation. Any proposed trigger for these flows
Debris flows and water tracks in northern Victoria Land, continental East Antarctica: a new terrestrial analogue site for gullies and recurrent slope lineae on Mars
Abstract Although the present environmental conditions on Mars prohibit the generation of significant volumes of liquid water, observations of several very young landforms, such as gullies and
Melt-water formed dark streaks on slopes of Haughton crater as possible Mars analogues
Abstract Haughton crater in the Canadian Arctic has been extensively used as a Mars (and lunar) analogue over the past 20 years. Here we report on small scale, dark, semi-seasonal slope streaks


Recurring slope lineae in equatorial regions of Mars
The presence of liquid water is a requirement of habitability on a planet. Possible indicators of liquid surface water on Mars include intermittent flow-like features observed on sloping terrains.
Formation of recurring slope lineae on Mars by rarefied gas-triggered granular flows
Active dark flows known as recurring slope lineae have been observed on the warmest slopes of equatorial Mars. The morphology, composition and seasonality of the lineae suggest a role of liquid water
Seasonal Flows on Warm Martian Slopes
Recurring slope lineae (RSL) are narrow, relatively dark markings on steep slopes; repeat images from the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment show them to appear and incrementally grow during warm seasons and fade in cold seasons.
Formation of recurring slope lineae by liquid brines on present‐day Mars
Recurring Slope Lineae (RSL) are small scale seasonal flow features identified by Mars Reconnaissance Orbiter that present several interesting characteristics such as an albedo contrast, seasonal
The water content of recurring slope lineae on Mars
Observations of recurring slope lineae (RSL) from the High‐Resolution Imaging Science Experiment have been interpreted as present‐day, seasonally variable liquid water flows; however, orbital
Recurring slope lineae and chlorides on the surface of Mars
Recurring Slope Lineae (RSL) are dark streaks that appear on steep slopes on the Martian surface. While their apparent movement suggests liquid flow, remote sensing studies have not found evidence of
Geologic context of recurring slope lineae in Melas and Coprates Chasmata, Mars
One of the major Mars discoveries of recent years is the existence of recurring slope lineae (RSL), which suggests that liquid water occurs on or near the surface of Mars today. These dark and narrow