OVERVIEW OF RECENT GEOLOGIC ACTIVITY AT THE CURIOSITY LANDING SITE
Additional features indicative of recent geomorphic activity include a number of seemingly pristine cracks and voids between polygonally fractured bedrock blocks in the Yellowknife Bay region, where Curiosity conducted several drilling experiments. While the majority of these fractures are filled with loose sediment, open holes were observed in a variety of locations and orientations within the region. In addition, an accumulation of dark, apparently fresh soil was observed alongside at least one bedrock block. Though no single explanation explains their occurrence, possible explanations include geologically recent subsurface volatile exchange and accumulated motion due to thermally-induced contraction/expansion. Although Curiosity attempted to detect potential motion over the diurnal cycle, no changes were detected at these locations, to the resolution of the rover's Mastcam instrument. Ongoing modeling work has begun to constrain plausible formation processes. Ultimately, Curiosity has observed abundant evidence of geologically recent surface modification at the Gale crater landing site, while detecting only limited surface changes over the timescales of the mission to date.