| South Sandwich Island |
The southern eight islands of the Sandwich Islands Group were discovered by James Cook in 1775; the northern three by Fabian Gottlieb von Bellingshausen in 1819. They were named "Sandwich Land" by Cook after the 4th Earl of Sandwich, 1st Lord of the Admiralty. The word "South" was added to distinguish them from the "Sandwich Islands", now known as "Hawaii".
The United Kingdom claimed South Georgia in 1775 and formally annexed both South Georgia and the South Sandwich Islands in 1908, grouping them with other British-held territory in Antarctica as the Falkland Islands Dependencies. Argentina later claimed the islands in dispute with the UK.
Argentina challenged British sovereignty in the Islands on several occasions. From January 25, 1955 through summer of 1956 Argentina maintained the summer station Teniente Esquivel at Ferguson Bay on the Southeastern coast of Thule Island.
From 1976 to 1982, Argentina maintained a naval base named Corbeta Uruguay, at Port Faraday, in the lee (southern East coast) of the same island. Although the British discovered the presence of the Argentine base in 1978, no effort was made to remove them until after the Falklands War. The base was eventually removed on June 20, 1982. |
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| Climate |
| Variable, with mostly westerly winds throughout the year interspersed with periods of calm; nearly all precipitation falls as snow. The South Sandwich Islands have prevailing weather conditions that generally make them difficult to approach by ship. |
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| Geography |
The South Sandwich Islands consist of 11 islands (from north to south): Zavodovski, Leskov (the smallest), Visokoi, Candlemas, Vindication, Saunders, Montagu (the largest), Bristol, Bellingshausen, Cook and Thule.
The South Sandwich Islands are 760km south east of South Georgia, and cover 310 sq m. Mt Belinda, the highest point, rises up to 1375m and can be found on Montagu Island.
Thule, Cook, Bristol, Montagu, Visokoi, Saunders and Candlemas are almost 80% covered by glaciers, and the remaining four have hardly any at all.
Even though these islands are more northerly than the South Shetlands (or even the South Orkneys), they have a much colder climate (due to the cold ocean current coming from the Weddell Sea).
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Visokoi Island - The Traversay Islands |
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| The South Sandwich Islands are a volcanic island arc caused by the subduction of the South American Plate beneath the South Sandwich Plate. The South Sandwich plate is one of the smallest geologic plates and is created at the South Sandwich spreading center. This small plate is less than 8 million years old and moves to the east at about 7 cm per year. The volcanic arc is younger than 5 million years. |
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| South Sandwich Islands Group |
| Thule Island - Thule Islands |
Thule Island, also called Morrell Island, is one of the southermost of the South Sandwich Islands, part of the grouping known as Southern Thule. It is named, on account of its remote location, after the mythical land of Thule, said by ancient geographers to lie at the extreme end of the earth, (the alternative name Morell Island is after Benjamin Morrell, US explorer and whaling captain).
Thule Island lies at 59°27′S 27°18′W, close to Cook Island and Bellingshausen Island. It is thought that Thule and Cook may have been a larger single island in the past, and there is evidence for a submerged crater between the two.
Steam from the summit crater lake and ash on the flank was reported in 1962. Volcanic heat keeps the crater on Thule Island free from ice.
The peak elevation is 3,525 feet (1,075m). In 1962, steam was rising from the water in Thule's summit crater and ash was noted on the island's southwest flank.
Argentina, in order to assert its claim over the South Sandwich Islands, established a research base on Thule Island called Corbeta Uruguay in the late 1970s. The base was occupied by British Forces in the aftermath of the Falklands War in 1982. |
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Thule Islands - Click to enlarge |
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| Bellingshausen Island - Thule Islands |
Bellingshausen Island (59°25′S 027°03′W) is one of the most southerly of the South Sandwich Islands, close to Thule Island and Cook Island, and forming part of the Southern Thule group. It is named after its discoverer, Russian Antarctic explorer Fabian von Bellingshausen (1778-1852).[clarification needed]
The island is a basaltic-andesite stratovolcano, and the latest crater, about 500 feet (150 metres) across and 200 feet (60 metres) deep, formed explosively some time between 1968 and 1984. Bellingshausen is a small youthful andesite cone with active fumaroles but no historic eruptions. |
| Cook Island - Thule Islands |
Cook Island (59°27′S 027°10′W) is the central island of Southern Thule, in the South Sandwich Islands. Southern Thule was discovered by a British expedition under Captain James Cook in 1775. The island was named for Cook by a Russian expedition under Bellingshausen, which explored the South Sandwich Islands in 1819-20.
Unlike most of the South Sandwich Islands, where most volcanoes are made of basalt, part of Cook Island is composed of andesite and dacite. |
| Bristol Island |
| Bristol Island is a compound volcano, made of several overlapping stratovolcanoes. Bristol Island is large (9 by 7 miles/14 by 12 km) and mostly ice covered. Havfruen Peak, on the east side of the island, has layers of cinders probably from an eruption in 1956, which produced glowing jets of material 600-900 feet (200-300m) above the volcano. Eruptions from other vents on the island were reported in 1823, 1935, 1936, and 1950. |
| Montagu Island |
Montagu Island is the largest of the South Sandwich Islands, located in the Weddell Sea off the coast of Antarctica at 58°25′S 26°23′W. The desolate, uninhabited island measures approximately 12 kilometres by 10, with over 90% of its surface permanently covered in ice.
The volcano Mount Belinda is its most notable geographic feature, rising to 1370 metres above sea level. Mount Belinda was believed to be inactive prior to the sighting of low-level ash emission and suspected lava effusion in 2002 by the British Antarctic Survey.
The island was first sighted by James Cook in 1775, and named after John Montagu, 4th Earl of Sandwich and the First Lord of the British Admiralty at the time of its discovery.
In November 2005, satellite images revealed that an eruption of Mount Belinda had created a 90 meter wide molten river flowing to the northern shorline of the island.
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Mt Belinda Volcano - Montagu Island |
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| The event has expanded the area of the island by 0.2 km², and provided some of the first scientific observations of volcanic eruptions taking place underneath an ice sheet. |
| Saunders Island |
Saunders Island was discovered in 1775 by Captain James Cook, who named it for Sir Charles Saunders, First Lord of the Admiralty. It was charted in greater detail by Bellingshausen in 1819, and in 1930 by DI personnel on the Discovery II.
Mount Michael is a mostly ice-covered stratovolcano. A crater (diameter: 2,300 feet, 700 m) and somma ridge are located at the summit. An explosive eruption was reported at the central vent in 1819. Vapor emissions were observed in 1820 and 1964. |
| Candlemas Island |
Discovered in 1775, Candlemas Island is a small uninhabited island in the South Sandwich Islands at 57°05′S 26°39′W. It lies about two miles from Vindication Island, separated by the Nelson Channel. On the northwest flank of the island is an active stratovolcano, Lucifer Hill, that showed signs of activity in 1911 and glowing lava flows during 1953–1954. Mount Andromeda and Mount Perseus are both glacier-covered peaks on the island. Mount Andromeda is the island's highest point, with an elevation of 1,804 feet (550 m).
Candlemas is an active stratovolcano. The north part of the volcano has numerous scoria cones and lava flows. Steam emissions, geysers, and hot pools have been reported several occasions. |
| Vindication Island |
| Vindication Island, just southwest of Candlemas Island, is the eroded remnant of former stratovolcanoes. Vindication Island is mostly ice-free. Unlike most of the South Sandwich Islands, where basalt makes the volcanoes, the north part of Candlemas is made of andesite and dacite. There is no evidence for activity at this volcano in the last 10,000 years. |
| Leskov Island - Traversay Islands |
| Leskov is small, mostly ice-free, stratovolcano with active fumaroles. Leskov is crescent-shaped and about 2,950 by 1,500 feet (900 by 460 m). An unusual feature of Leskov is its position - its not along the same curved line as the other South Sandwich volcanoes. Most of Leskov is made of thick lava flows. Unlike most of the South Sandwich Islands, which are made of basalt, Leskov Island is made of porphritic andesite. |
| Visokoi Island - Traversay Islands |
Visokoi Island is about 5 by 3.7 miles (8 by 6 km). There are basaltic scoria cones on the east slopes of the island. Plumes were noted at the volcano in 1830 and 1930.
Hodson is a large, mostly ice-covered stratovolcano. |
| Zavodovski - Traversay Islands |
Zavodovski Island is about 3 miles (5 km) in diameter. Tephra makes about 50% of the island. Fresh lava was reported on the volcano in 1819. Very active fumaroles have been reported on numerous occasions. Explosive eruptions that produced basaltic cinders are suspected in 1823, 1830, and 1908.
Mount Curry is the stratovolcano that forms the island of Zavodovski.
On Zavodovski Island is the largest penguin colony in the world. About two million Chinstrap Penguins come to breed on the snow-free slopes of this live volcano. But emperor penguins stick it out on the ice.
At the water's edge they are nervous as leopard seals patrol this border. These seals are Antarctica's equivalent of polar bears. As winter closes in again and the ice begins to freeze, male emperor penguins trek south, away from the open sea, to spend the dark months of winter out on the ice. |
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Chinstrap Penguins below Mt Curry Zavodovski Island |
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| Protector Shoal |
| Protector Shoal is a submarine volcano. The volcano erupted in March of 1962. The euption produced great volumes of rhyolitic pumice. The pumice raft covered an area of at least 2,000 square miles! Pumice from the eruption eventually drifted west to New Zealand. Unlike most of the South Sandwich Islands, which are made of basalt, Protector Shoal is the only volcano in the arc that has erupted rhyolite. |
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| Volcanic Activity |
In late October 2006, Mount Belinda, on Montagu Island in the remote South Sandwich Islands, continued emitting volcanic ash and lava in what had become a five-year-long eruption.
The volcano’s activity intensified in September 2005, producing a lava field that traveled 3.5 kilometers (2 miles) from Mount Belinda to the sea. That lava eruption left a 500-meter-wide lava delta, still visible more than a year later.
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