81-696: Annenkov Island is an island in South Georgia and the South Sandwich Islands , to the west of the main island of South Georgia . The Pickersgill Islands are to its southeast. It is irregularly shaped and 4 miles (6.4 km) long and 650 m (2,130 ft) high, lying 8 miles (13 km) off the south-central coast of South Georgia. The island was discovered in January 1775 by a British expedition under James Cook , who named it Pickersgills Island for Lieutenant Richard Pickersgill of
162-576: A tundra ( ET ) in Köppen climate classification . Typical daily maximum temperatures in South Georgia at sea level are around 0 °C (32 °F) in winter (August) and 8 °C (46.4 °F) in summer (January). Winter minimum temperatures are typically about −5 °C (23 °F) and rarely dip below −10 °C (14 °F). Annual precipitation in South Georgia is about 1,500 mm (59.1 in), much of which falls as sleet or snow, which
243-459: A basaltic magma must crystallize specific minerals that are then removed from the melt. This removal can take place in a variety of ways, but most commonly this occurs by crystal settling. The first minerals to crystallize and be removed from a basaltic parent are olivines and amphiboles . These mafic minerals settle out of the magma, forming mafic cumulates. There is geophysical evidence from several arcs that large layers of mafic cumulates lie at
324-563: A component of the Martian crust . The name andesite is derived from the Andes mountain range, where this rock type is found in abundance. It was first applied by Christian Leopold von Buch in 1826. Andesite is an aphanitic (fine-grained) to porphyritic (coarse-grained) igneous rock that is intermediate in its content of silica and low in alkali metals . It has less than 20% quartz and 10% feldspathoid by volume, with at least 65% of
405-696: A content of 57% to 63% silica and not more than about 6% alkali metal oxides. This places the andesite in the O2 field of the TAS classification . Basaltic andesite , with a content of 52% to 57% silica, is represented by the O1 field of the TAS classification but is not a distinct rock type in the QAPF classification. Andesite is usually light to dark grey in colour, due to its content of hornblende or pyroxene minerals. but can exhibit
486-565: A geological survey by the British Antarctic Survey (BAS), 1972–73. Except where noted, the following features were named by UK-APC. Annenkov island is a rocky island with a number of ridges and hills, particularly toward the centre. The highest point is Olstad Peak, which rises to 650 m (2,130 ft). Olstad Peak was named for Norwegian zoologist and expedition member Ola Olstad. An irregular ridge called Bareback Ridge extends north from Olstad Peak. The name stems from
567-523: A group of islands rather than a single body of land. The name was chosen in honour of John Montagu, 4th Earl of Sandwich , who was First Lord of the Admiralty. The word "South" was later added to distinguish them from the "Sandwich Islands", now known as the Hawaiian Islands . Southern Thule , at the south end of the island chain, is the southernmost land on Earth outside the area covered by
648-448: A more pleasant climate than the exposed western side. The prevailing weather conditions generally make the islands difficult to approach by ship, though the north coast of South Georgia has several large bays which provide good anchorage. Sunshine, as with many South Atlantic Islands, is low, at a maximum of just 21.5%. This amounts to around 1,000 hours of sunshine annually. The local topography , however, also contributes significantly to
729-492: A new list of three criteria was created for deciding new names within the territory. During British captain James Cook 's navigation of the islands, he set a standard for the adoption of new names in the territory based on four categories: expedition sponsors, the names of officers and crew, notable contemporary events, and descriptive names referring to the physical nature of the place or geographic formation. This standard
810-472: A number of locations have been given Spanish names, including Punta Carbón and Punta Hueca . An Argentine naval station called Corbeta Uruguay was clandestinely built on Thule Island , South Sandwich Islands , on 7 November 1976 before its abandonment by Argentine forces following their defeat in the Falklands War . South Georgia and the South Sandwich Islands are a collection of islands in
891-783: A separate territory. The King Edward Point base, which had become a small military garrison after the Falklands War, returned to civilian use in 2001 and is now operated by the British Antarctic Survey . Captain James Cook discovered the southern eight islands of the Sandwich Islands Group in 1775, although he lumped the southernmost three together, and their status as separate islands was not established until 1820 by Fabian Gottlieb von Bellingshausen . The northern three islands were discovered by Bellingshausen in 1819. The islands were tentatively named "Sandwich Land" by Cook, although he also commented that they might be
SECTION 10
#1732772875186972-534: A subducting slab generates magma resembling high-magnesium andesites. Notable stonemasonry structures built with andesite include: In 2009, researchers revealed that andesite was found in two meteorites (numbered GRA 06128 and GRA 06129) that were discovered in the Graves Nunataks icefield during the US Antarctic Search for Meteorites 2006/2007 field season. This possibly points to
1053-408: A very small non-permanent population resides on South Georgia. There are no scheduled passenger flights or ferries to or from the territory, although visits by cruise liners to South Georgia are increasingly popular, with several thousand visitors each summer. The United Kingdom claimed sovereignty over South Georgia in 1775 and the South Sandwich Islands in 1908. The territory of "South Georgia and
1134-649: A wide range of shading. Darker andesite can be challenging to distinguish from basalt, but a common rule of thumb , used away from the laboratory, is that andesite has a color index less than 35. The plagioclase in andesite varies widely in sodium content, from anorthite to oligoclase , but is typically andesine , in which anorthite makes up about 40 mol% of the plagioclase. The pyroxene minerals that may be present include augite , pigeonite , or orthopyroxene . Magnetite , zircon , apatite , ilmenite , biotite , and garnet are common accessory minerals. Alkali feldspar may be present in minor amounts. Andesite
1215-566: A year, most of which is spent on fishery protection and research. All fisheries are regulated and managed in accordance with the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) system. Andesite Andesite ( / ˈ æ n d ə z aɪ t / ) is a volcanic rock of intermediate composition . In a general sense, it is the intermediate type between silica -poor basalt and silica-rich rhyolite . It
1296-573: Is Alison Blake , who took the post on 1 July 2022. The executive, based in Stanley, Falkland Islands, is made up of a Chief Executive, three Directors, two managers, and a Business Support Officer. The Financial Secretary and Attorney General of the territory are appointed ex officio similar appointments in the Falkland Islands' government. On the island itself, Government Officers manage vessel visits, fishing and tourism, and represent
1377-499: Is "not a single shrub nor any vegetation" on the island. 500 wandering albatross pairs breed here. South Georgia and the South Sandwich Islands South Georgia and the South Sandwich Islands ( SGSSI ) is a British Overseas Territory in the southern Atlantic Ocean . It is a remote and inhospitable collection of islands, consisting of South Georgia and a chain of smaller islands known as
1458-629: Is a fragment of some greater land-mass now vanished and was probably a former extension of the Andean system . Smaller islands and islets off the coast of South Georgia Island include: These remote rocks are also considered part of the South Georgia Group: The South Sandwich Islands comprise 11 mostly volcanic islands (excluding tiny satellite islands and offshore rocks), with some active volcanoes. They form an island arc running north–south in
1539-435: Is a small lake located in the southeast of the island. The lake is fed by meltwater and is bounded to the west by an alluvial fan , from which the name is derived. The island is surrounded by reefs, including Hauge Reef and Low Reef to the east. A site of special scientific interest , Annenkov always was and remains one of the few rat -free islands of the South Georgia archipelago, and as Bellinghausen lamented, there
1620-873: Is buried at Grytviken. The ashes of another noted Antarctic explorer, Frank Wild , who had been Shackleton's second-in-command on the Imperial Trans-Antarctic Expedition, were interred next to Shackleton in 2011. Argentina claimed South Georgia in 1927. The basis of this claim and of a later claim in 1938 to the South Sandwich Islands has been questioned. During the Second World War , the Royal Navy deployed an armed merchant vessel to patrol South Georgian and Antarctic waters against German raiders, along with two four-inch shore guns (still present) protecting Cumberland Bay and Stromness Bay, which were operated by volunteers from among
1701-415: Is fine-grained ( aphanitic ) to porphyritic in texture, and is composed predominantly of sodium-rich plagioclase plus pyroxene or hornblende . Andesite is the extrusive equivalent of plutonic diorite . Characteristic of subduction zones, andesite represents the dominant rock type in island arcs . The average composition of the continental crust is andesitic. Along with basalts, andesites are
SECTION 20
#17327728751861782-524: Is mountainous and largely barren. Eleven peaks rise to over 2,000 metres (6,600 ft) high, their slopes furrowed with deep gorges filled with glaciers; the largest is Fortuna Glacier . The highest peak is Mount Paget in the Allardyce Range at 2,934 metres (9,626 ft). Geologically, the island consists of gneiss and argillaceous schists with occasional tuffs and other sedimentary layers from which fossils have been recovered. The island
1863-443: Is possible the entire year. Inland, the snow line in summer is at an altitude of about 300 m (984 ft). Westerly winds blow throughout the year interspersed with periods of calm—indeed, in 1963, 25% of winds were in the calm category at King Edward Point, and the mean wind speed of around 8 knots (9.2 mph; 15 km/h) is around half that of the Falkland Islands. This gives the eastern side of South Georgia (leeward side)
1944-518: Is so characteristic of the Earth's unique plate tectonics that the Earth has been described as an "andesite planet". During subduction, the subducted oceanic crust is subjected to increasing pressure and temperature, leading to metamorphism . Hydrous minerals such as amphibole , zeolites , or chlorite (which are present in the oceanic lithosphere ) dehydrate as they change to more stable, anhydrous forms, releasing water and soluble elements into
2025-412: Is the northwest point of Annenkov Island. Mislaid Rock, first named on a 1931 British Admiralty chart, lies offshore to the southwest. The name appears to be first used on a 1931 British Admiralty chart. On the eastern arm of the island is a tussock -covered ridge called Albatross Crest, named for the wandering albatross ( Diomedea exulans ) which nests here. On the north coast of the eastern tip of
2106-472: Is usually porphyritic , containing larger crystals ( phenocrysts ) of plagioclase formed prior to the extrusion that brought the magma to the surface, embedded in a finer-grained matrix . Phenocrysts of pyroxene or hornblende are also common. These minerals have the highest melting temperatures of the typical minerals that can crystallize from the melt and are therefore the first to form solid crystals. Classification of andesites may be refined according to
2187-666: Is −19.4 °C (−2.9 °F), but Bird Island just −11.4 °C (11.5 °F). The seas surrounding South Georgia are cold throughout the year due to the proximity of the Antarctic Circumpolar Current . They usually remain free of pack ice in winter, though thin ice may form in sheltered bays, and icebergs are common. Sea temperatures drop to 0 °C (32 °F) in late August and rise to around 4 °C (39.2 °F) only in early April. The South Sandwich Islands are much colder than South Georgia, being farther south and more exposed to cold outbreaks from
2268-453: The Andes , magma often pools in the shallow crust creating magma chambers. Magmas in these reservoirs become evolved in composition (dacitic to rhyolitic) through both the process of fractional crystallization and partial melting of the surrounding country rock . Over time as crystallization continues and the system loses heat, these reservoirs cool. In order to remain active, magma chambers must have continued recharge of hot basaltic melt into
2349-546: The Antarctic Treaty . Argentina claimed the South Sandwich Islands in 1938, and challenged British sovereignty in the Islands on several occasions. From 25 January 1955 to mid-1956, Argentina maintained the summer station, "Teniente Esquivel" ( es ) at Ferguson Bay on the southeastern coast of Thule Island . Argentina maintained a naval base ( Corbeta Uruguay ) from 1976 to 1982, in the lee (southern east coast) of
2430-554: The South Sandwich Islands . South Georgia is 165 kilometres (103 mi) long and 35 kilometres (22 mi) wide and is by far the largest island in the territory. The South Sandwich Islands lie about 700 kilometres (430 mi) southeast of South Georgia. The territory's total land area is 3,903 km (1,507 sq mi). The Falkland Islands are about 1,300 kilometres (810 mi) west from its nearest point. The South Sandwich Islands are uninhabited, and
2511-662: The Thatcher peninsula , was originally given the Swedish name Majviken meaning " May Bay" but was later altered into its current Norwegian spelling. In addition, numerous German placenames were also adopted in recognition of the German International Polar Year Expedition of 1882-1883 and an earlier American whaling voyage in 1877-1878 carrying Austrian painter Heinrich Klutschak , with Klutschak Point and Schrader Glacier commemorating
Annenkov Island - Misplaced Pages Continue
2592-452: The feldspar in the rock consisting of plagioclase . This places andesite in the basalt /andesite field of the QAPF diagram . Andesite is further distinguished from basalt by its silica content of over 52%. However, it is often not possible to determine the mineral composition of volcanic rocks, due to their very fine grain size, and andesite is then defined chemically as volcanic rock with
2673-442: The shield volcanoes characteristic of basalt, with its much lower viscosity resulting from its lower silica content and higher eruption temperature. Block lava flows are typical of andesitic lavas from composite volcanoes. They behave in a similar manner to ʻaʻā flows but their more viscous nature causes the surface to be covered in smooth-sided angular fragments (blocks) of solidified lava instead of clinkers. As with ʻaʻā flows,
2754-486: The 1982 Falklands War , during which Argentine forces briefly occupied the island. Argentina continues to claim sovereignty over South Georgia and the South Sandwich Islands as part of the Tierra del Fuego, Antártida e Islas del Atlántico Sur Province . Toothfish are vital to the islands' economy; as a result, Toothfish Day is celebrated on 4 September as a bank holiday in the territory. The island of South Georgia
2835-677: The Antarctic continent. They are also surrounded by sea ice from the middle of May to late November (even longer at their southern end). Recorded temperature extremes at South Thule Island have ranged from −29.8 to 17.7 °C (−21.6 to 63.9 °F). Executive power is vested in the monarch of the United Kingdom and is exercised by the Commissioner , a post held by the Governor of the Falkland Islands . The current Commissioner
2916-522: The King Edward Point meteorological station (often generically and less accurately called Grytviken) on the sheltered eastern side of South Georgia is 28.8 °C (83.8 °F). Conversely, the highest recorded temperature at Bird Island on the windward western side is a mere 14.5 °C (58.1 °F). As one might expect, the sheltered eastern side can also record lower winter temperatures—the absolute minimum temperature for King Edward Point
2997-669: The Norwegian whalers. The base at King Edward Point was expanded as a research facility in 1949–1950 by the British Antarctic Survey , which until 1962 was called the Falkland Islands Dependencies Survey. The Falklands War was precipitated on 19 March 1982 when a group of Argentinians (most of them Argentine Marines in mufti ), posing as scrap-metal merchants, occupied the abandoned whaling station at Leith Harbour on South Georgia. On 3 April, Argentine troops attacked and occupied Grytviken . Among
3078-489: The South Atlantic Ocean. Most of the islands, rising steeply from the sea, are rugged and mountainous. At higher elevations, the islands are permanently covered with ice and snow. The South Georgia Group lies about 1,390 kilometres (860 mi; 750 nmi) east-southeast of the Falkland Islands, at 54°–55°S, 36°–38°W. It comprises South Georgia Island itself, by far the largest island in the territory, and
3159-495: The South Sandwich Islands is limited. The territory has revenues of £6.3 million, 80% of which is derived from fishing licences (2020 figures). Other sources of revenue are the sale of postage stamps and coins, tourism, and customs and harbour dues. Fishing takes place around South Georgia and in adjacent waters in some months of the year, with fishing licences sold by the territory for Patagonian toothfish , cod icefish and krill . Fishing licences bring in millions of pounds
3240-582: The South Sandwich Islands" was formed in 1985; previously, it had been governed as part of the Falkland Islands Dependencies . Argentina claimed South Georgia in 1927 and claimed the South Sandwich Islands in 1938. Argentina maintained a naval station, Corbeta Uruguay , on Thule Island in the South Sandwich Islands from 1976 until 1982 when it was closed by the Royal Navy . The Argentine claim over South Georgia contributed to
3321-716: The United Kingdom issued further letters patent that established constitutional arrangements for its possessions in the South Atlantic. The letters covered South Georgia, the South Orkneys , the South Shetlands , the South Sandwich Islands, and Graham Land . The claim was extended in 1917 to include a sector of Antarctica reaching to the South Pole . In 1909, an administrative centre and residence were established at King Edward Point on South Georgia, near
Annenkov Island - Misplaced Pages Continue
3402-492: The absence of surficial material and vegetation from its top and sides. Towards the centre of the island, the McPherson Crags rise to 460 m (1,510 ft). They were named for Ray McPherson, a British Antarctic Survey (BAS) officer. To the east, Lawther Knoll is a rounded, scree -covered hill rising to 315 metres (1,030 ft). It was named for BAS geologist Eric Lawther. First Point, charted and named by DI,
3483-408: The base of the crust. Once these mafic minerals have been removed, the melt no longer has a basaltic composition. The silica content of the residual melt is enriched relative to the starting composition. The iron and magnesium contents are depleted. As this process continues, the melt becomes more and more evolved eventually becoming andesitic. Without continued addition of mafic material, however,
3564-717: The commanding officers of the Argentine garrison was Alfredo Astiz , a captain in the Argentine Navy who was convicted years later of crimes against humanity committed during the Dirty War in Argentina. The island was recaptured by British forces on 25 April, in Operation Paraquet . In 1985, South Georgia and the South Sandwich Islands ceased to be administered as a Falkland Islands Dependency and became
3645-456: The expedition ship HMS Resolution . It was rediscovered in 1819 by a Russian expedition under Fabian Gottlieb von Bellingshausen on the Vostok , who, thinking he was the discoverer of the island, named it Annenkov Island, in honour of Lt. Mikhail D. Annenkov (1794 – 1839), officer on the expedition ship. The name Pickersgill has become established for a group of islands 15 miles (24 km) to
3726-664: The first land-based whaling station and first permanent habitation at Grytviken in 1904. It operated through his Argentine Fishing Company , which settled in Grytviken. The station operated until 1965. Whaling stations operated under leases granted by the Governor of the Falkland Islands . The seven stations, all on the north coast with its sheltered harbours, were, from the west to east: The whaling stations' tryworks were unpleasant and dangerous places to work. One
3807-464: The first landing. He claimed the territory for the Kingdom of Great Britain , naming it the "Isle of Georgia" in honour of King George III of the United Kingdom . British arrangements for the government of South Georgia were established under 1843 British letters patent . In 1882–1883 a German expedition for the first International Polar Year set up its base at Royal Bay on the southeast side of
3888-482: The government 'on the ground'. A summer Deputy Postmaster runs the Post Office at Grytviken during the tourism season. As no permanent inhabitants live on the islands, no legislative council and no elections are needed. The UK Foreign, Commonwealth and Development Office (FCDO) manages the foreign relations of the territory. Since 1982, the territory celebrates Liberation Day on 25 April. The constitution of
3969-522: The historical presence of Norwegian whalers , including Hestesletten ("horse's plain"), Skrap Skerries ("skrapskjaer" or "skrapskjar"), Grytviken ("Pot Bay"), and Elsehul ("Else's hole"), as well as a few whaling stations such as Godthul ("good hollow"). The first person to be born in South Georgia (and south of the Antarctic Convergence ), Solveig Gunbjørg Jacobsen , was also Norwegian. The small cove Maiviken , located in
4050-431: The island, Spilite Arch is a sea-worn arch formed by a pillar of rock 30 m (98 ft) high joined to the coastal cliffs by a spilite sill . Towards the south end of the island, Pettigrew Scarp is an escarpment nearly 0.5 nmi (0.93 km) long, which terminates to the southwest in a ridge, and in the northeast by three rock pinnacles. It was named for BAS geologist Timothy Pettigrew. South West Point marks
4131-461: The island. The scientists of this group observed the transit of Venus and recorded waves produced by the 1883 eruption of Krakatoa . Seal hunting at South Georgia began in 1786 and continued throughout the 19th century. The waters proved treacherous and a number of vessels were wrecked there, such as Earl Spencer , in late 1801. South Georgia became a base for whaling beginning in the 20th century. A Norwegian, Carl Anton Larsen , established
SECTION 50
#17327728751864212-494: The islands that immediately surround it and some remote and isolated islets to the west and east-southeast. It has a total land area of 3,756 square kilometres (1,450 sq mi), including satellite islands, but excluding the South Sandwich Islands which form a separate island group. South Georgia Island lies at 54°15′S 36°45′W / 54.250°S 36.750°W / -54.250; -36.750 and has an area of 3,528 square kilometres (1,362 sq mi). It
4293-406: The low insolation . A study published during the early 1960s indicated that sunshine recording instruments remained significantly obscured throughout the year and entirely obscured during June. It was estimated that the theoretical sunshine exposure minus obstructions would be around 14% at Bird Island and 35% at King Edward Point – or, in hourly terms, ranging from around 650 hours in
4374-437: The melt will eventually reach a rhyolitic composition. This produces the characteristic basalt-andesite-rhyolite association of island arcs, with andesite the most distinctive rock type. Partially molten basalt in the mantle wedge moves upwards until it reaches the base of the overriding crust. Once there, the basaltic melt can either underplate the crust, creating a layer of molten material at its base, or it can move into
4455-523: The molten interior of the flow, which is kept insulated by the solidified blocky surface, advances over the rubble that falls off the flow front. They also move much more slowly downhill and are thicker in depth than ʻaʻā flows. Though andesite is common in other tectonic settings, it is particularly characteristic of convergent plate margins . Even before the Plate Tectonics Revolution , geologists had defined an andesite line in
4536-492: The most abundant phenocryst . For example, if hornblende is the principal phenocryst mineral, the andesite will be described as a hornblende andesite . Andesite lava typically has a viscosity of 3.5 × 10 cP (3.5 × 10 Pa⋅s) at 1,200 °C (2,190 °F). This is slightly greater than the viscosity of smooth peanut butter . As a result, andesitic volcanism is often explosive, forming tuffs and agglomerates . Andesite vents tend to build up composite volcanoes rather than
4617-510: The overlying wedge of mantle. Fluxing water into the wedge lowers the solidus of the mantle material and causes partial melting. Due to the lower density of the partially molten material, it rises through the wedge until it reaches the lower boundary of the overriding plate. Melts generated in the mantle wedge are of basaltic composition, but they have a distinctive enrichment of soluble elements (e.g. potassium (K), barium (Ba), and lead (Pb)) which are contributed from sediment that lies at
4698-441: The overriding plate in the form of dykes . If it underplates the crust, the basalt can (in theory) cause partial melting of the lower crust due to the transfer of heat and volatiles. Models of heat transfer, however, show that arc basalts emplaced at temperatures 1100–1240 °C cannot provide enough heat to melt lower crustal amphibolite . Basalt can, however, melt pelitic upper crustal material. In continental arcs, such as
4779-487: The region 56°18'–59°27'S, 26°23'–28°08'W, between about 350 and 500 mi (300 and 430 nmi; 560 and 800 km) southeast of South Georgia. The archipelago comprises Candlemas , Vindication , Saunders , Montagu , Bristol , Bellingshausen , Cook and Thule discovered by Cook, and Thule. The northernmost of the South Sandwich Islands form the Traversay Islands and Candlemas Islands groups, while
4860-554: The rock in rough weather and low visibility, passing within 1 nautical mile (2 km) of heavy breakers. The island also contains some named freshwater lakes mapped and named by the British Antarctic Survey in 1972–73. Intrusion Lake, a 0.2 miles (0.32 km) long lake, is located north-northeast of Olstad Peak in the center of the island; it was named because its irregular shape is controlled by several intrusions of andesite along its north shore. Fan Lake
4941-485: The same island. Although the British discovered the presence of the Argentine base in 1976, protested and tried to resolve the issue by diplomatic means, no effort was made to remove them by force until after the Falklands War . The base was removed on 20 June 1982. The sole official language of the territory is English, which is widely spoken amongst residents currently and used for nearly all administrative functions in
SECTION 60
#17327728751865022-639: The southeast—see Pickersgill Islands . Discovery Investigations (DI) surveyed the area in the period 1926–30. The Norvegia expedition [ no ] under Harald Horntvedt visited the area between 1927 and 1928. The island was surveyed by the South Georgia Survey between 1951–1957. Many of its features were named by the United Kingdom Antarctic Place-Names Committee (UK-APC) following these surveys. Others were named following
5103-419: The southernmost make up Southern Thule . The three largest islands – Saunders , Montagu , and Bristol – lie between the two. The islands' highest point is Mount Belinda (1,370 m or 4,495 ft) on Montagu Island. The fourth highest peak, Mount Michael (990 m or 3,248 ft) on Saunders Island has a persistent lava lake , known to occur at only eight volcanoes in
5184-482: The southwest point of Annenkov Island, and appears to have been first named on a chart based upon DI surveys undertaken in the period 1926–30. East of this point, Rustad Bay indents the island's southwest coast. It was named for Norwegian biologist Ditlef Rustad. West of the point, Horror Rock lies 3.5 nautical miles (6 km) offshore. It was named from the circumstances of the rock's discovery by HMS Owen (K640) on February 21, 1961. The ship avoided striking
5265-541: The system. When this basaltic material mixes with the evolved rhyolitic magma, the composition is returned to andesite, its intermediate phase. Evidence of magma mixing is provided by the presence of phenocrysts in some andesites that are not in chemical equilibrium with the melt in which they are found. High-magnesium andesites ( boninites ) in island arcs may be primitive andesites, generated from metasomatized mantle. Experimental evidence shows that depleted mantle rock exposed to alkali fluids such as might be given off by
5346-467: The territory (adopted 3 October 1985), the manner in which its government is directed and the availability of judicial review were discussed in a series of litigations between 2001 and 2005 (see, in particular, Regina v. Secretary of State for Foreign and Commonwealth Affairs (Appellant) ex parte Quark Fishing Limited [2005] UKHL 57 ). Although its government is directed by the FCDO, it was held that, since it
5427-521: The territory include Morrell Point , Wasp Point , Pacific Point , and Comer Crag . Prominent Russian-language names chosen by Bellingshausen include the Traversay Islands , Zavodovski Island , and Visokoi Island ( высокий meaning "high"). There is also a Lowland Scots language presence within the topography of the territory, with some locations being named after notable Scottish individuals, such as Geikie Glacier and Allardyce Range , amongst others . A number of placenames were influenced by
5508-610: The territory. Although English is used in the majority of government functions, the islands' motto Leo Terram Propriam Protegat is in Latin and is translated as "May the Lion protect his own land". The adoption of new placenames was governed by the Place-names Ordinance of 1956 and Place-names Regulation of 1957 until 11 September 2020, when a representative was appointed to the regional Antarctic Place-names Committee and
5589-585: The top of the subducting plate. Although there is evidence to suggest that the subducting oceanic crust may also melt during this process, the relative contribution of the three components (crust, sediment, and wedge) to the generated basalts is still a matter of debate. Basalt thus formed can contribute to the formation of andesite through fractional crystallization, partial melting of crust, or magma mixing, all of which are discussed next. Intermediate volcanic rocks are created via several processes: To achieve andesitic composition via fractional crystallization ,
5670-475: The two others, Tom Crean and Frank Worsley , went on to cover 22 miles (35 km) over the spine of the mountainous island to reach help at Stromness whaling station. The remaining 22 members of the expedition, who had stayed on Elephant Island, were subsequently rescued. In January 1922, during a later expedition , Shackleton died on board ship while moored in King Edward Cove, South Georgia. He
5751-453: The two trips. There has been a Spanish language presence in the territory for a significant amount of time, with the whaling company Compañía Argentina de Pesca operating in the territory for approximately 60 years. However, there are relatively few Spanish names within the territory currently, in part due to ongoing sovereignty dispute over the islands by Argentina, although since the beginning of Argentine Antarctic Expeditions in 1952,
5832-563: The west to 1,500 hours in the east. This illustrates the effect the Allardyce Range has in breaking up cloud cover. Mountain winds rise over the western slopes of the mountains of South Georgia and down the eastern side and become much warmer and drier due to the Föhn effect ; this produces the most pleasant conditions when temperatures can occasionally rise to over 20 °C (68 °F) on summer days. The highest temperature recorded at
5913-488: The western Pacific that separated basalt of the central Pacific from andesite further west. This coincides with the subduction zones at the western boundary of the Pacific Plate . Magmatism in island arc regions comes from the interplay of the subducting plate and the mantle wedge , the wedge-shaped region between the subducting and overriding plates. The presence of convergent margins dominated by andesite
5994-578: The whaling industry, the stations were abandoned. Apart from a few preserved buildings such as the South Georgia Museum and Norwegian Lutheran Church at Grytviken , only their decaying remains survive. From 1905, the Argentine Meteorological Office cooperated in maintaining a meteorological observatory at Grytviken under the British lease requirements of the whaling station until these changed in 1949. In 1908,
6075-430: The whaling station of Grytviken. A permanent local British administration and resident magistrate exercised effective possession , enforcement of British law , and regulation of all economic, scientific, and other activities in the territory, which was then governed as the Falkland Islands Dependencies . In about 1912, what is according to some accounts the largest whale ever caught, a blue whale of 110 feet (34 m),
6156-468: The world. The South Sandwich Islands are uninhabited, though a permanently staffed Argentine research station was located on Thule Island from 1976 to 1982. Automatic weather stations are on Thule Island and Zavodovski . To the northwest of Zavodovski Island is the Protector Shoal , a submarine volcano. The climate is classified as polar, and the weather is highly variable and harsh, making
6237-655: Was acting as an agent of the Crown in right of South Georgia and the South Sandwich Islands rather than in right of the UK, its decisions under that direction could not be challenged as if they were in law decisions of a UK government department; thus the European Convention on Human Rights did not apply. Commercial sealing occurred on the islands between 1817 and 1909. During that period 20 visits are recorded by sealing vessels. Economic activity in South Georgia and
6318-455: Was called "a charnel house boiling wholesale in Vaseline" by an early 20th-century visitor. Tim Flannery wrote that its "putrid vapors [resembled] the pong of bad fish, manure, and a tanning works mixed together", and noted one bizarre peril: "A rotting whale could fill with gas to bursting, ejecting a fetus the size of a motor vehicle with sufficient force to kill a man." With the end of
6399-458: Was first sighted and visited in April 1675 by Anthony de la Roché , a London merchant and (despite his French name) an Englishman, who spent a fortnight in one of the island's bays. The island appeared as Roche Island on early maps. The commercial Spanish ship León , operating out of Saint-Malo , sighted it on 28 June or 29 June 1756. James Cook circumnavigated the island in 1775 and made
6480-421: Was landed at Grytviken. In April 1916, Ernest Shackleton 's Imperial Trans-Antarctic Expedition became stranded on Elephant Island , some 800 miles (1,300 km) southwest of South Georgia. Shackleton and five companions set out in a small boat to summon help, and on 10 May, after an epic voyage, they landed at King Haakon Bay on South Georgia's south coast. While three stayed at the coast, Shackleton and
6561-487: Was mostly followed by later visitors in the region, including by explorers from different countries, such as Russian explorer Fabian Gottlieb von Bellingshausen , who selected six new names within the territory in his 1819-1821 Antarctic expedition. Locations currently bearing names selected by Cook include Clerke Rocks , Possession Bay , and Bay of Isles , amongst others. Additional English names given many years after in recognition of past visits by American whalers in
#185814