Stefansson Sound

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Stefansson Sound is a sea channel in the British Antarctic Territory extending north to south separating Hearst Island from the Black Coast of Graham Land.

The sound was photographed from the air by Wilkins on 20 December 1928 and named 'Stefansson Strait' after Dr Vilhjalmur Stefansson (1879-1962), an Arctic explorer, ethnologist and polar specialist Steffanson, of Canadian birth and Icelandic parentage, had been the leader of expeditions to the Canadian Western Arctic, 1906-07 and 1908-12, and Commander of the Canadian Arctic Expedition of 1913-18 which discovered three islands of the Queen Elizabeth Islands. He was also the author of 'The Friendly Arctic' (1921) and other works.

Wilkins described the feature as a wide channel in c. 70°40'S, trending south-west and then west from the Weddell Sea into the Bellingshausen Sea, and separating Graham Land from the mainland of Antarctica. The Norwegian whale gunners Søren Beckmann and Gustav Mathisen in February 1924, reached Marguerite Bay in their whale catchers and reported the existence of a very deep bay, or a channel extending eastwards to the Weddell Sea. The feature was reportedly identified from the air by Ellsworth on 21 November 1935, when it "appeared to be not more than three miles wide". Following study of Ellsworth's photographs and logs, it was concluded that the result of his flight "seems to be to compress Stefansson Strait and shift it northward as compared with Wilkins' reconnaissance map. Its eastern entrance seems to lie mainly north of the 70th parallel".[1]

In October 1936, a the British Graham Land Expedition sledge party reached 72°03'S on George VI Sound and established that no strait separates Graham Land from mainland Antarctica to the north of this latitude. In November-December 1936, another the British Graham Land Expedition sledge party crossed from the Wordie Ice Shelf almost to the Weddell Sea in c. 69°45'S, discovered and surveyed a large transverse depression in 69°25'S, and a broad glacier (Clifford Glacier) in 70°25'S, but saw no evidence of a strait. Further study of Ellsworth's photographs, in comparison with Wilkins' photographs and in conjunction with the British Graham Land Expedition preliminary reports, led to the suggestion that the feature named by Wilkins was "a major embayment and not a through channel"; the name in the form 'Stefansson Inlet' was applied to the feature, which was shown running SW for c. 90 km from its N entrance in c. 69°30'S. This adjustment entailed re-orientation of Wilkins' photographs P and Q with which Wilkins, in June 1938, was reported to have concurred. During chart compilation by the US Hydrographic Office in 1939 the "major valley depression" (the Mercator Ice Piedmont) shown by Joerg was wrongly identified with the large transverse depression lying north of the British Graham Land Expedition 1936 sledge route. As a result of this misidentification, all the other features on Joerg's map were moved southwards and Stefansson Inlet was shown as an inlet opening towards the north between 70°05' and 70°30'S. From further study of Wilkins' and Ellsworth's photographs and logs, it was suggested that the feature thought by Ellsworth to be Stefansson Strait must in fact have been the Lurabee Glacier, but it was concluded that there was insufficient evidence "to give a definite location to Stefansson `Strait' or `Inlet'". Later examination of Ellsworth's photographs (for example by Joerg in 1936) showed that his 'Stefansson Strait' was in fact Mobiloil Inlet. In December 1940, the feature photographed from the air by Wilkins was surveyed from the ground and further photographed from the air by the United States Antarctic Service, and it was shown as a strait separating Hearst Island from the mainland coast, but it was not recognized as Wilkins' 'Stefansson Strait': it was called Boggs Strait after S W Boggs (whose name is found in Cape Boggs). In reviewing USHO chart 2562, 1943, Hinks concluded that Stefansson Inlet was wrongly placed; he suggested that the Stefansson Strait of Wilkins' photographs was "nothing but the Weddell Sea", but that the Stefansson Strait which Wilkins had described as cutting through Graham Land was probably the large transverse depression north of the British Graham Land Expedition sledge route. Later comparison of Wilkins' photograph Q with the United States Antarctic Service air and ground photographs proved that Wilkins' Stefansson Strait and the United States Antarctic Service's 'Boggs Strait' were in fact the same feature.

Following survey by the Falkland Islands Dependencies Survey- with the Ronne Antarctic Research Expedition from "Stonington Island" in November 1947, the identity of the present feature was finally established.

Location

References

  • Joerg, 1936, maps p.455, p.460