Geophysical Research Letters

Candidate ice-rich material within equatorial craters on Mars



[1] The floors and walls of many mid-latitude (∼30–60°) craters on Mars appear to be mantled by relatively young material(s) with distinct morphology and erosional properties. Collectively, this material (“fill”) is often interpreted as ice-rich, with emplacement and modification related to climatological processes. Here, I document material and associated landforms within 38 craters between 4–13°S in the Sinus Sabaeus region that appear morphologically similar to material and landforms within mid-latitude craters. These equatorial/mid-latitude materials may also share a common composition and emplacement mechanism. Near-surface ice is unstable at equatorial latitudes under present conditions, suggesting that emplacement could have occurred under different climate conditions in the past. High-obliquity (35–45°) general circulation model (GCM) simulations show surface ice accumulation in Sinus Sabaeus and Tharsis, where similar material and landforms have been documented. These observations are consistent with the hypothesis that past obliquity-driven climate change resulted in equatorward volatile migration on Mars.