Geomorphology of periglacial landforms within a small crater in Terra Cimmeria, Mars

Abstract

We present the results of geomorphological mapping of a small crater (35.88°S, 147.59°E) in Terra Cimmeria, Mars. We identified and assessed (qualitatively and quantitatively) many landforms in the crater which resemble features formed in terrestrial periglacial environments. These landforms include gullies and their depositional fans, stripes, polygons, moraine-like features, and possible solifluction lobes. We measured slopes of the fans in a HiRISE DEM and determined average values between 12° and 17°, typical for young fans on Mars. The crater has been filled with concentric crater fill (stratigraphically older) and/or a latitude dependent mantle (LDM) (younger). We deduce that a former glacier was active in this crater, which pushed up the crater floor material into moraine-like structures. A LMD was later deposited and subsequently eroded in areas, possibly due to aeolian processes, mass wasting, and the formation of gullies and alluvial fans. Polygons formed on the eroded walls of gullies (possibly indicating freeze/thaw processes). Through geomorphic mapping we can unravel the history of geologic processes in this crater and try to reconstruct the evolution of the very recent Martian climate.