Data Repository for Degradation of Rustic Canyon Crater in Gale Crater, Mars Crater, Mars.

The Rustic Canyon crater is a degraded, impact structure on the north flank of Mt. Sharp in Gale crater. The crater is irregular in plan form, ~20 m across NW-SE and ~30 m across NE-SW and lacks a raised-rim. Using images and a Digital Terrain Model derived from a rover orthomosaic of the crater, we evaluated the amount and processes of degradation based upon current versus expected original crater morphology for a crater formed by a primary, fragmenting primary, or secondary impact event. We conclude that the crater is modified by predominantly aeolian degradation responsible for between ~50 cm and up to ~1-2 m of down-wasting, ~1 m to several m of wall back-wasting, and 10s of cm of local infilling by aeolian drift. Nevertheless, some patchy ejecta remains and limits the amount of overall degradation that has modified the original crater form. The degradation required to modify a deeper crater formed by a primary impactor and the absence of interior relief associated with rims or “septa” between multiple contributing craters formed by a fragmenting impactor contrast with the appearance of Rustic Canyon and indicate it is probably a secondary impact crater. Locally prevailing NE winds accomplish vertical and horizontal erosion rates of 0.1 m/Myr and 1-2 m/Myr, respectively, and can produce the observed degraded crater morphology in as little as a few Ma to most likely 10-20 Ma, but as many as 50-60 Ma.