Cornwall Island

Cornwall Island (2358 km2, 910 sq mi) is located in the Queen Elizabeth Islands (Sverdrup group) of the Canadian High Arctic Archipelago, Nunavut Territory. The landscape is similar to the surrounding islands, with gentle hills covered with sparse tundra vegetation. The interior of the island contains several plateaus rising to 250 m elevation. Soil cover is primarily composed of exposed sandstone and siltstone from the Mesozoic Sverdrup Basin group. Igneous rock has intruded to form diabase dykes and sills that resist erosion and produce narrow ridges and occasional isolated highlands, including the highest point on the island, Mt Nicolay (416 m). A thin veneer of glacial sediment composed of local sediments, gravel, and boulders covers the bedrock, although mud is the most common soil material. Thick successions of marine sediment are found in valley bottoms and were deposited after the late Wisconsinan ice sheet retreated, and the sea filled the (then) depressed landscape to 120 m during the early Holocene (approximately 9000 years before present).

Like much of the region, the climate is cold and dry. During the short melt season (June-August), snow melts rapidly and floods the rivers for 2-3 weeks. Thereafter, rivers recede and are low through the rest of the summer, only rising in response to rare rainstorms. There are no glaciers, but snow frequently remains all summer in sheltered locations and the large lakes remain partially ice covered in late summer in most years. The entire island is underlain by continuous permafrost and the soil surface thaws to a depth of 0.3-1.0 m during the summer. Cold summers, underlying permafrost, and muddy soils combine to make surface travel on foot and vehicle particularly difficult.

The tundra vegetation is best developed in low-lying, wet locations and is composed primarily of stunted willow (Salix arctica) and other sedges. Wildlife is also sparse and limited to a small number of species. Peary caribou and muskox occur in small herds, and support a small population of Arctic wolves, although animal populations vary due to winter food availability. Other mammals include Arctic fox, snowshoe hare, and lemmings, while very occasional polar bears and walruses are found near the coastline. Migratory birds, particularly black-tailed jaegers nest during the spring and remain during the summer. Arctic char is found in some coastal lakes.

No permanent settlements or facilities are located on the island and visitors are rare. Cornwall Island was found and named by Edward Belcher in 1852 during the search for the missing British explorer John Franklin. The next recorded visit was by Otto Sverdrup's companions Gunnar Isachsen and Sverre Hassel during a 1901 sledge trip into the northwestern Arctic. Mapping and initial geological studies were carried out in the 1950s and several exploratory wells were drilled on the central north and south coasts during petroleum exploration in the 1970s, although no reserves were identified.

Scott Lamoureux See also Nunavut; Queen Elizabeth Islands

Further Reading

Balkwill, H.R., Geology of Amund Ringnes, Cornwall, and Haig-Thomas Islands, District of Franklin, Memoir 390, Ottawa: Geological Survey of Canada, 1983 Berton, P., The Arctic Grail: the Quest for the North West Passage and the North Pole, 1818-1909, Toronto: McClelland and Stewart, 1988 Edlund, S.A. & B.T. Alt, "Regional congruence of vegetation and summer climate patterns in the Queen Elizabeth Islands, Northwest Territories, Canada." Arctic, 42 (1989): 3-23 Hodgson, D.A., Surficial Materials and Geomorphological Processes, Western Sverdrup and Adjacent Islands, District of Franklin, Paper 81-9, Ottawa: Geological Survey of Canada, 1982

Lamoureux, S.F. & J.H. England, "Late Wisconsinan glaciation of the northwest sector of the Canadian Arctic Archipelago." Quaternary Research, 54 (2000): 1882-1888

Maxwell, J.B., The Climate of the Canadian Arctic Islands and Adjacent Waters, Hull: Canadian Government Publishing Centre, 1980

Sverdrup, O.N., Arctic Adventures, London: Longmans, 1959 Woo, M.-K., "Hydrology of a drainage basin in the Canadian High Arctic." Annals of the Association of American Geographers, 73 (1983): 577-596

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