关于这张图
During the 2018 Mars dust storm, we obtained a clear view of the summit of the giant volcano Elysium Mons. We see the western rim and floor of the caldera, and a chain of pits (called a "catena") extending from the caldera towards the north. The chain of pits likely formed by volcanic processes, such as the collapse of a lava tube after it drained. Or by a tectonic process, such as a rift in the rocks below that drained loose material from the surface. An unexpected feature of this catena is the presence of avalanches in two of the pits (marked A and B in the cutout, with the uphill direction…
