Mound on Mars. Coloured satellite image of a conical mound (lower left) on the surface of Mars' North Polar Layered Deposits (NPLD). The NPLD is composed of ice-rich layers that are exposed during erosion to produce troughs and scarps. The mound is roughly 40 metres high and may be the remnant of a buried crater.The NPLD may provide clues to the planet's climate history. Image obtained by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter (MRO) on 2nd September 2008. The width of this image is roughly 1.3 kilometres across.