Pack-ice on Mars?

This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, during orbit 32, shows what appears to be a dust-covered frozen sea near the Martian equator. It shows a flat plain, part of the Elysium Planitia. The scene is a few tens of kilometres across, centred on latitude 5º North and longitude 150º East.