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 .
4-572: The Holmes Hills ( 72°8′S 63°25′W / 72.133°S 63.417°W / -72.133; -63.417 ) are a group of ridges and nunataks rising to about 1,700 metres (5,600 ft) between Runcorn Glacier and Beaumont Glacier , bounded to the southwest by the Brennecke Nunataks , in south-central Palmer Land , Antarctica. They were mapped by the United States Geological Survey from aerial photographs taken 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
12-751: The U.S. Navy , 1966–69, and surveyed by the British Antarctic Survey , 1972–73. In association with the names of continental drift scientists grouped in this area, the hills were named by the Advisory Committee on Antarctic Names in 1978 after Scottish geologist Arthur Holmes , Professor of Geology at the University of Edinburgh , 1943–56. [REDACTED] This article incorporates public domain material from "Holmes Hills" . Geographic Names Information System . United States Geological Survey . This Palmer Land 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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