The most prominent feature in the new topographic map is a broad convex dome approximately 500 kilometers in diameter with a maximum height of 3 kilometers above the surrounding plains. The South Polar Dome is abruptly truncated along one margin by a prominent 1 kilometer high scarp. The scarp and depression are interpreted as evidence that the layered deposits were originally much more extensive but have retreated due to erosion. Evidence for retreat of the North Polar Cap has also been cited by the MOLA team. Topographic Maps of the South Polar Region of Mars Figure 5a Digital Elevation Model of the South Polar Cap of Mars.
Brighter areas are higher in elevation.
Figure 5b Color-coded Digital Elevation Model of the South Polar Cap of Mars. Red is high, blue is low. Rougly 3 kilometers of relief is portrayed. Figure 6 Sketch map showing major physiographic regions of the south polar region. The medium-weight outline is the edge of the layered deposits.