A nunatak (from Inuit nunataq ) is the summit or ridge of a mountain that protrudes from an ice field or glacier that otherwise covers most of the mountain or ridge. They often form natural pyramidal peaks . Isolated nunataks are also called glacial islands, and smaller nunataks rounded by glacial action may be referred to as rognons .
4-460: The Lully Foothills ( 70°49′S 69°38′W / 70.817°S 69.633°W / -70.817; -69.633 ) are a large group of peaks and nunataks extending 15 nautical miles (28 km) in a northeast–southwest direction between Vivaldi Glacier and the LeMay Range in the west-central part of Alexander Island , Antarctica . Apparently first seen from the air and roughly mapped by
8-654: Is a stub . You can help Misplaced Pages by expanding it . Nunatak The word is of Greenlandic origin and has been used in English since the 1870s. The term nunatak is typically used in areas where a permanent ice sheet is present and the ridge protrudes above the sheet. Nunataks present readily identifiable landmark reference points in glaciers or ice caps and are often named. While some are isolated, they can also form dense clusters, such as Queen Louise Land in Greenland. Nunataks are generally angular and jagged, hampering
12-878: The United States Antarctic Service in 1940, they were remapped in detail from air photos taken by the Ronne Antarctic Research Expedition , 1947–48, by D. Searle of the Falkland Islands Dependencies Survey in 1960. The foothills were named by the UK Antarctic Place-Names Committee after Jean-Baptiste Lully , a French composer . [REDACTED] This article incorporates public domain material from "Lully Foothills" . Geographic Names Information System . United States Geological Survey . This Alexander Island location article
16-467: The formation of glacial ice on their tops, although snow can accumulate on them. This can contrast strongly with the softer contours of the glacially eroded land after a glacier retreats. They are not greatly affected by frost weathering , given the low frequency of freeze-thaw cycles in areas of ice caps and ice sheets. Typically nunataks are the only places where plant life can survive on ice sheets or ice caps. Lifeforms on nunataks are often isolated by
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