Peneus Patera

An unusual layer of smooth material covers the flanks of the volcano Peneus Patera just south of the Hellas Basin, seen here in a crater on the patera rim. Though smooth on its upper surface, the layer is pitted by a process of erosion that produces steep scarps facing the south pole and more gentle slopes in the direction of the equator. The style of erosion of the smooth layer suggests that ice of some form plays a role in shaping this terrain.