RIDGED BEDROCK TERRAIN IN GALE CRATER, MARS

Gale crater, which the Mars Science Laboratory Curiosity rover has been exploring since 2012, hosts several examples of enigmatic ridged bedrock terrain. One example is the “Washboard” texture on top of Greenheugh pediment and the Naukluft plateau, which has a similar appearance to the ridged texture of a washboard when viewed from orbit. Several mechanisms for the formation of this washboard and other ridged terrains have been proposed, ranging from depositional processes (e.g., the ridges being exhumed fossilized bedforms) to erosional processes (e.g., modern wind-eroded bedrock ridges, possibly related to fracturing or vein formation in the bedrock).

Curiosity has recently visited three instances of ridged terrains, the Naukluft Plateau, Glen Torridon, and the “gator-back” terrain at the Greenheugh Pediment. Prior to this exploration, information on these ridges was limited to orbital data. This work has identified several additional ridged areas within the same Mound-Skirting Unit as the examples encountered by the rover, as well as others farther up the central mound of the crater (Aeolis Mons/Mount Sharp).

This work aims to further characterize the instances of this terrain in Gale crater, by combining orbital data and in situ information to understand the variation between instances of the bedrock ridges. By examining the bedrock in which they form, the ridge morphology, the geographic distribution of the ridges, their relationship to other aeolian features, and modern and ancient wind regimes, we aim to better understand their origin and evolution.