Glacial lake Glacial lake A glacial lake is a lake with origins in a melted glacier. They are formed when a glacier erodes the land, and then melts, filling the hole or space that it has created. Near the end of the last glacial period, roughly 10,000 years ago, glaciers began to retreat. A retreating glacier often left behind large deposits of ice in hollows between drumlins or hills. As the ice age ended, these melted to create lakes. This is apparent in the Lake District in Northwestern England where post-glacial sediments are normally between 4 and 6 metres deep. These lakes
Blue ice (glacial) Zealand in January 2011. Blue ice is exposed in areas of the Antarctic where there is no net addition or subtraction of snow. That is, any snow that falls in that area is counteracted by sublimation or other losses. These areas have been used as runways (e.g. Wilkins Runway, Novolazarevskaya, Patriot Hills Base Camp) due to their hard surface, which is suitable for aircraft fitted with wheels rather than skis. Blue ice (glacial) Blue ice occurs when snow falls on a glacier, is compressed, and becomes part of the glacier. Air bubbles are squeezed out and ice crystals enlarge, making