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55-700: The boundary between the South American and Antarctic plates can be divided into three parts of which the SAAR forms the eastern third: The first stretches from the Chile triple junction in the Chile Trench at 46°S to the western Straits of Magellan at 52°S. Since 15  Ma , the oceanic crust of the Antarctic plate is being slowly subducted (20–24 mm/a (0.79–0.94 in/year)) under South America along this trench which

110-594: A Romanian explorer, was one of the most successful entrepreneurs in the region. Granted rights by the Argentine government to exploit any gold deposits he found in Tierra del Fuego, Popper has been identified as a central figure in the Selk'nam genocide . Following contact with Europeans, the native Selk'nam and Yaghan populations were greatly reduced by unequal conflict and persecution by settlers, by infectious diseases to which

165-500: A glacier-carved depression in a pull-apart basin that has developed along the Magallanes-Fagnano Fault zone. Podzols and inceptisols occur beneath Nothofagus betuloides forests in Tierra del Fuego. The Tierra del Fuego region has a subpolar oceanic climate ( Köppen climate classification Cfc ) with short, cool summers and long, wet, moderately mild winters: the precipitation averages 3,000 mm (118 in)

220-528: A group of many islands, including Cape Horn and Diego Ramírez Islands . Tierra del Fuego is divided between Argentina , which controls the eastern part of the main island and a few small islands in the Beagle Channel, and Chile , which controls the remaining land area. The southernmost extent of the archipelago is just north of latitude 56°S . The earliest known human settlement in Tierra del Fuego dates to approximately 8,000 BC. Europeans first explored

275-406: A main island, Isla Grande de Tierra del Fuego , often simply called Tierra del Fuego or Isla Grande, with an area of 48,100 km (18,572 sq mi), and a group of smaller islands. Of the main island the westernmost 29,484.7 km (11,384 sq mi , 61.43%) belongs to Chile, and 18,507.3 km (7,146 sq mi , 38.57%) belongs to Argentina. The archipelago is divided by an east–west channel,

330-453: A plains region ( Spanish : Región de las Planicies Orientales ) plus a sub-Andean zone in-between the last two zones ( Spanish : Región Sub-Andina Oriental ). The geology of the archipelago is influenced by the effects of the Andean orogeny and the repeated Pleistocene glaciations . The geology of the island can be divided into large east–west-oriented units. The southwestern islands of

385-526: A rate of only 0.3 cm/yr. The brief opening of small extensional basins south of Tierra del Fuego initiated the opening of the Drake Passage around 49 Ma after which the spreading rate increased eight-fold to 2.4 cm/yr. As the Antarctic—South American plate motion changed from north to north-west during this period, oceanic crust in the north-west Weddell Sea started to subduct on

440-574: A separate microplate called 'Sur' (Spanish for 'South') north of the SAAR. The southern part of this Sur microplate has probably also been broken off and is subducting independently under the South Sandwich Arc. The break-up of Gondwana began in the Mid- to Late Jurassic in what is today the Mozambique Basin east of Africa, whereas the South American and African plates started to break apart during

495-570: A topographic swell, acts as a barrier between the north and south half of the Chile Trench. The continental basement of southern Chile is mainly formed of metasedimentary and metavolcanic rocks of Paleozoic age intruded by Cretaceous and Tertiary, acidic, I-type plutonic rocks of the Patagonian Batholith. In the southern-central Chilean margin, the sediment in the Chile trench is confined to

550-471: A year in the far west, but precipitation decreases rapidly towards the eastern side. Temperatures are steady throughout the year: in Ushuaia they hardly surpass 9 °C (48 °F) in summers and average 0 °C (32 °F) in winters. Snowfall can occur in summer. The cold and wet summers help preserve the ancient glaciers . The southernmost islands possess a sub-antarctic climate typical of tundra that makes

605-437: Is a prominent area to watch rare, endemic dolphins, and the less-studied pygmy right whales . Pinnipeds inhabiting the areas include South American sea lions ( Otaria flavescens ), South American fur seals ( Arctophoca australis ), the carnivorous and seal-eating leopard seals ( Hydrurga leptonyx ), and gigantic southern elephant seals ( Mirounga leonine )  – the largest extant marine mammal that

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660-421: Is also home to the lizard with the world's southernmost distribution, Liolaemus magellanicus . North American beavers , introduced during the 1940s, have proliferated and caused considerable damage to the island forests. The governments have established a wide-reaching program to trap and kill beavers in Tierra del Fuego. Like the mainland of Chile and Argentina to the north, this archipelago boasts some of

715-467: Is an important process that leads to mountain building and the growth of continents, but it is also associated with the destruction of forearc material. The impact of topographic features, such as topographic features of mountain ranges and faulting, is one important mechanism. An impact between a spreading ridge and a continental forearc can result in a thermal pulse within the forearc. This thermal pulse can be quantified using apatite fission track data and

770-707: Is currently extending northward. In the central part, between the Straits of Magellan and the South Sandwich Trench , the two large continental plates are separated by the Scotia plate and a number of smaller plates east of it. During the past 40 Ma (or since the opening of the Drake Passage ) the South Sandwich Trench has been migrating eastward due to the evolution of a back-arc basin , effectively consuming

825-507: Is known to underlie some of the oil wells in northern Tierra del Fuego. The Magallanes–Fagnano Fault , a sinistral strike slip fault crosses the southern part of the main island from west to east. It is an active fault , located inside and parallel to the Fuegian fold and thrust belt , and marks the boundary between a southern belt of Paleozoic meta sediments and a northern Mesozoic belt of sedimentary sequences. Fagnano Lake occupies

880-520: Is not a cetacean . The following table lists islands over 1 km . Area figures are from the USGS unless otherwise specified. Today, the main economic activities of the archipelago are fishing, extraction of natural gas and oil , sheep farming , and ecotourism . Tourism is gaining increasing importance as it attracts numerous upmarket visitors. Much of the tourism is based on "southernmost" claims: for example, both Ushuaia and Puerto Williams claim to be

935-549: The Beagle Channel , immediately south of the main island. The largest islands south of the Beagle Channel are Hoste and Navarino . The western part of the main island, and almost all the other islands, belong to Chile. They are part of the Magallanes y Antártica Chilena Region , the capital and chief town of which is Punta Arenas , situated on the mainland across the strait. The largest Chilean towns are Porvenir , capital of

990-787: The Northeast Georgia Rise (today north of the Scotia plate) and the Maud Rise (off Antarctica) were located next to the Agulhas Plateau (south of South Africa) where the Bouvet hotspot formed the Southern Ocean Large Igneous Province (112–93 Ma). The Bouvet triple junction, today considered an R-F-F (ridge-fault-fault) type triple junction , was an R-R-R type before anomaly 28 (c. 64 Ma), which means that before

1045-652: The oceanic trench . Tierra del Fuego Tierra del Fuego ( / t i ˈ ɛər ə d ɛ l ˈ f w eɪ ɡ oʊ / , Spanish: [ˈtjera ðel ˈfweɣo] ; Spanish for " Land of Fire ", rarely also Fireland in English) is an archipelago off the southernmost tip of the South American mainland , across the Strait of Magellan . The archipelago consists of the main island, Isla Grande de Tierra del Fuego , with an area of 48,100 km (18,572 sq mi), and

1100-453: The "southernmost city in the world". On the Argentine side of Tierra del Fuego, the government has promoted the establishment of several electronic companies via tax exemptions, particularly in the city of Río Grande . Energy production is a crucial economic activity. On the Argentine side of Tierra del Fuego during the period 2005–2010, petroleum and natural gas extraction contributed 20% of

1155-509: The 1940s Chile and Argentina lodged their Antarctic claims. In the 1950s, the Chilean military founded Puerto Williams . In the 1960s and 1970s, sovereignty claims by Argentina over Picton, Lennox, and Nueva Islands in Tierra del Fuego led the two countries to the brink of war. In 1986, the Argentine congress decided that the Argentine part of Tierra del Fuego should be a new province. This happened in 26 April 1990. The archipelago consists of

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1210-587: The American, African, and Antarctic lithospheric plates which has geographical coordinates of 55°S, 0°E. North of the SAAR the South Sandwich plate consumes the South American plate at a rate of 65.8 mm/yr driven by back-arc extension. This fast subduction has broken off the southern part of the South American plate between the north-eastern end of the South Sandwich Arc and the Mid-Atlantic Ridge, leaving

1265-500: The Chile Rise became consumed by subduction and the more northerly regions of the Antarctic plate begun to subduct beneath Patagonia so that the Chile triple junction advanced gradually to its present position in front of Taitao Peninsula at 46°15'. The South American plate is moving away from the Nazca plate and moving in a direction to the north of the Chile ridge spreading center, while

1320-579: The Chile Rise or Chile Ridge, and the Chile Ridge, with the Nazca-Antarctic spreading center being at 46.5° S, the Chile Rise or Chile Ridge being more prominent in the south. Additionally around 14 Ma, the Chile Rise collided with the South American continental plate . The high relief topography caused the trench to be devoid of sediment at the Chile-South America junction. Subduction accretion

1375-527: The Chile Rise. The trench is unusually poor in sediments north of the JFR, but is heavily sedimented south of the Chile triple junction. The accretionary prism is confined between the two large topographic features, the Chile Rise and the JFR. The northern Chilean margin is poor in sediments due to low sediment supplies from the Andes and the presence of the JFR, which acts as a barrier to the transport of trench sediments from

1430-544: The Chilean Province of Tierra del Fuego , located on the main island, and, on Navarino Island, Puerto Williams , which is the capital of the Antártica Chilena Province . Puerto Toro lies a few kilometers south of Puerto Williams. Arguably, it is the southernmost village in the world. The mostly uninhabited islands north and west of the main island are part of Magallanes Province . The eastern part of

1485-614: The Cretaceous and Cenozoic. The western part of the SAAR is dominated by the earthquake-intensive South Sandwich island arc , fore-arc , and trench . East of these structures the SAAR is composed of a series of north–south-oriented ridge crests, median valleys, and east–west-oriented transform faults. The major transform faults (from the east to the west) are the Konrad (displacement about 190 km),the Bullard (displacement more than 700 km),

1540-842: The Early Cretaceous. Between these events neither the Mid-Atlantic Ridge nor the Bouvet triple junction existed and the SAAR formed a continuous ridge together with the Southwest Indian Ridge . Around 106 Ma the eastern end of the Falkland Plateau separated from the Agulhas Bank , opening the South Atlantic which, however, remained an enclosed basin north of the Falkland Plateau until 85–83 Ma. Around 97 Ma

1595-431: The Nazca plate is subducting under the South American plate at a rate of about 80–90 mm/a north of the triple junction. The triple junction of the Chile Ridge, the Chile Trench and the Antarctic plate collided about 14 Ma ago near the latitude of Tierra del Fuego . Since then it has migrated north, with the actual triple junction now located at 46°12'S.The Chilean margin consists of the Nazca-Antarctic spreading center,

1650-456: The Nazca, Antarctic, and South American plates meet at the trench. The Antarctic plate started to subduct beneath South America 14 million years ago in the Miocene epoch forming the Chile triple junction. At first the Antarctic plate subducted only in the southernmost tip of Patagonia , meaning that the Chile triple junction lay near the Strait of Magellan . As the southern part of Nazca plate and

1705-497: The SAAR. The third eastern part, i.e. the 'SAAR proper', has two long and several shorter transform faults separating short north-to-south-directed ridge crests. The motion in the SAAR is currently c. 20 mm/a (0.79 in/year) westward but it was originally closer to north–south. It can be inferred, based on fracture zone topography and magnetic anomalies in the Weddell Sea , that this change in direction occurred during

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1760-587: The Scotia plate started to develop in the Mid-Tertiary, only ridges and transform faults separated Africa, Antarctica, and South America. The north–south motion of Antarctica relative to Africa and South America before anomaly 28 changed to a slow east–west clockwise motion around 60 Ma, an abrupt change coincident with change in triple junction configuration. During the Late Paleocene–Early Eocene Antarctica and South America separated at

1815-452: The Volcano (displacement about 100 km), and the southernmost South Sandwich (displacement up to 320 km) transform faults. The topography of the SAAR is extreme, with valleys reaching 1.5–2 km (0.93–1.24 mi) deeper than adjacent ridges in average and maximum depth exceeding 3 km. The SAAR is more shallow near the Bouvet triple junction. The Bouvet triple junction is between

1870-649: The archipelago, including Cape Horn , are part of the South Patagonian Batholith , while the Cordillera Darwin and the area around the Beagle Channel form the principal mountain range hosting the highest mountains. The Magallanes fold and thrust belt extends north of Almirantazgo Fjord and Fagnano Lake , and north of this lies the Magallanes foreland, an old sedimentary basin that hosts hydrocarbon reserves . Orthogneiss dated at 525 million years

1925-507: The eastern side of the Drake land bridge—the eastward migration of the South Sandwich Trench had begun. 58°S 15°W  /  58°S 15°W  / -58; -15 Chile triple junction The Chile triple junction (or Chile margin triple junction ) is a geologic triple junction located on the seafloor of the Pacific Ocean off Taitao and Tres Montes Peninsula on

1980-646: The finest trout fishing in the world. Sea-run brown trout often exceed 9 kg (20 lb), particularly in rivers such as the Rio Grande and the San Pablo, and in the Lago Fagnano . Waters adjacent to Tierra del Fuego are very rich in cetacean diversity. Sightings of southern right whales in Tierra del Fuego have increased in the 2000s, humpbacks , and some others such as blue whales , southern fins , southern seis , and southern minkes . Beagle Channel

2035-620: The growth of trees impossible. Some areas in the interior have a polar climate. Regions in the world with similar climates to southern Tierra del Fuego are: the Aleutian islands , Iceland , the Alaska Peninsula , the Faroe Islands , Macquarie Island , and the Heard and McDonald Islands . Only 30% of the islands have forests, which are classified as Magellanic subpolar . The northeastern portion of

2090-562: The heavy winds and cool summers in the Faroe Islands did not allow the growth of trees from other regions in the world. The imported trees are used ornamentally, as curtains against wind, and to fight erosion caused by storms and grazing in the Faroe Islands. Among the most notable animals in the archipelago are austral parakeets , gulls , guanacos , South American foxes , kingfishers , Andean condors , king penguins , owls , and firecrown hummingbirds . Isla Grande de Tierra del Fuego

2145-631: The indigenous people had no immunity , and by mass transfer to the Salesian mission of Dawson Island. Despite the efforts of the missionaries, many natives died. Today, only a few Selk'nam remain . Some of the few remaining Yaghan have settled in Villa Ukika in Navarino Island ; others have scattered throughout Chile and Argentina. Following the signing of the Boundary Treaty of 1881 , Tierra del Fuego

2200-513: The islands during Ferdinand Magellan 's expedition of 1520. Tierra del Fuego and similar namings stem from sightings of the many bonfires that the natives built. Settlement by those of European descent and the displacement of the native populations did not begin until the second half of the nineteenth century, at the height of the Patagonian sheep farming boom and of the local gold rush . Today, petroleum extraction dominates economic activity in

2255-526: The main island and a few small islands in the Beagle Channel belong to Argentina. They are part of the Tierra del Fuego, Antarctic Territory and South Atlantic Islands Province , whose capital is Ushuaia , the largest city of the archipelago. The other important city in the region is Río Grande on the Atlantic coast. The Cordillera Darwin in the southwestern part of the main island contains many glaciers that reach

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2310-417: The main island between 1883 and 1909. Numerous Argentines, Chileans, and Croatians settled on the main island, leading to increased conflicts with native Selk'nam . These late nineteenth century gold rushes led to the founding of numerous small settlements by immigrants, such as the Argentine settlements of Ushuaia and Río Grande and the Chilean settlements of Porvenir and Puerto Toro . Julius Popper ,

2365-452: The nineteenth century. Missionary Thomas Bridges (1842–1898) learned the native language and compiled a 30,000-word Yaghan grammar and dictionary while he worked at Ushuaia. It was published in the 20th century and is considered an important ethnological work. An 1879 Chilean expedition led by Ramón Serrano Montaner reported large amounts of placer gold in the streams and river beds of Tierra del Fuego. This prompted massive immigration to

2420-405: The north of Tierra del Fuego, while tourism, manufacturing, and Antarctic logistics are important in the south. The earliest human settlement occurred approximately 8,000 BC. The Yaghan were some of the earliest known humans to settle in Tierra del Fuego. Archeological sites with characteristics of their culture have been found at locations such as Navarino Island . The name Tierra del Fuego

2475-441: The ocean. While Mount Darwin had previously been thought to be the tallest mountain in the archipelago, this distinction now belongs to the unofficially named Monte Shipton at 2,580 metres (8,460 feet). The topography of Tierra del Fuego can be divided into four regions: an outer archipelago region ( Spanish : Región Archipielágica ) to the south and west, a mountainous region in the south ( Spanish : Región Cordillerana ),

2530-526: The only forests in the world to have developed in a climate with such cold summers. Tree cover extends very close to the southernmost tip of South America. Winds are so strong that trees in wind-exposed areas grow into twisted shapes, inspiring people to call them "flag-trees". Tree vegetation extends to the southern tip of the region, Isla Hornos , although the Wollaston Islands are mostly covered by subantarctic tundra except in wind sheltered areas where

2585-669: The region is made up of steppe and cool semi-desert. Six species of tree are found in Tierra del Fuego: canelo or winter's bark ( Drimys winteri ); Maytenus magellanica ; Pilgerodendron uviferum , the southernmost conifer in the world; and three kinds of southern beech : Nothofagus antarctica ; Nothofagus pumilio ; and the evergreen Nothofagus betuloides . Several kinds of fruit grow in open spaces in these forests, such as beach strawberry ( Fragaria chiloensis var. chiloensis forma chiloensis ) and calafate ( Berberis buxifolia ), which have long been gathered by both Native Americans and residents of European descent. They are

2640-504: The southern Chile trench to the north. Taitao Peninsula lies near the triple junction and various geological features, such as the Taitao ophiolite , are related to the dynamics of the triple junction. Ridge and trench collisions are clear indications of the subduction history around the Pacific Ocean and are likely a dominant mechanism of ophiolite positioning. This results in a rapid sinking and spreading along with magmatic activity near

2695-672: The southern coast of Chile . Here three tectonic plates meet: the South American plate , the Nazca plate and the Antarctic plate . This triple junction is unusual in that it consists of a mid-oceanic ridge , the Chile Rise , being subducted under the South American plate at the Peru–Chile Trench . The Chile triple junction is the boundary between the Chilean Rise and the Chilean margin, where

2750-499: The thermal maturity of organic carbon in the forearc sediment. Several authors have suggested that subduction erosion or slip during earthquakes may be responsible for the uplift of the Coastal Cordillera, a trench-parallel morphostructural system in north Chile. The Juan Fernández Ridge (JFR) is a prominent feature on the oceanic Nazca lithosphere located west of the Chile Trench. The O'Higgins seamount group, surrounded by

2805-449: The trees can survive. Forests from Tierra del Fuego have expanded beyond local importance. These forests have been a source of trees that have been transplanted abroad in places with similar climate, but which originally were devoid of trees, such as the Faroe Islands and nearby archipelagos. Most species were gathered from the coldest places in Tierra del Fuego, mainly sites with tundra borders. This effort resulted in positive changes, as

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2860-644: The voyage were taken to London to meet the king and queen and were, for a time, celebrities. They returned to Tierra del Fuego in the Beagle with FitzRoy and Charles Darwin , who made extensive notes about his visit to the islands. During the second half of the nineteenth century, Salesian Catholic missions were established in Río Grande and Dawson Island . Anglican missionaries, who had established missions on Keppel Island in 1855, established new missions in 1870 at Ushuaia . These missions continued to operate through

2915-456: Was divided between Argentina and Chile; previously, it had been claimed in its entirety by both countries. In 1945, a division of Chilean CORFO (Spanish acronym for Production Development Corporation), engaged in oil exploration , discovered oil in northern Tierra del Fuego. Extraction began in 1949 and, in 1950, the Chile state-owned ENAP (National Petroleum Company) . Until 1960, most oil extracted in Chile came from Tierra del Fuego. During

2970-595: Was given by the Portuguese explorer Ferdinand Magellan while sailing for the Spanish Crown in 1520; he was the first European to visit these lands. He believed he was seeing the many fires ( fuego in Spanish) of the indigenous inhabitants, which were visible from the sea, and that the "Indians" were waiting in the forests to ambush his armada . In 1525, Francisco de Hoces was the first to speculate that Tierra del Fuego

3025-472: Was one or more islands rather than part of what was then called Terra Australis . Francis Drake in 1578 and a Dutch East India Company expedition in 1616 learned more about the geography. The latter expedition named Cape Horn at Hornos Island . On his first voyage with HMS  Beagle in 1830, Robert FitzRoy picked up four native Fuegians , including " Jemmy Button " ( Orundellico ) and Yokcushlu , and brought them to England. The three who survived

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