关于这张图
This 2.5-kilometer diameter crater observed by NASA's Mars Reconnaissance Orbiter has been significantly altered from the usual bowl-shaped appearance we associate with craters. Material has covered significant portions of the ejecta and filled in the crater. This fill material has since been subject to erosion -- like boulders weathering out of the slopes -- and the crater rim is also highly irregular. This crater is located in Elysium Planitia, an area dominated by volcanic processes. It is likely that the crater fill material is volcanic in origin, and possible that the rim was etched by l…
