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50-596: 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

100-594: 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

150-462: A specific gravity above 2.58. The separation of the valuable minerals from the most common non-economic mineral, quartz , depends on the difference in specific gravity / density .The weathering process allows for the accumulation of placer minerals, while less dense material such as quartz are swept away. Hardness allows placer minerals to resist mechanical breakdown and loss of mass from abrasion during transport. A hardness greater than quartz

200-512: A cement like substance in which material like gold are found. Wind action blows sand and dirt away leaving the deposits close to the surface. Historically, aeolian placers have been mined by hand with simple tools by miners due to the proximity to the surface, and small concentration. Aeolian placers are common in Australia and the Western United states, where the climate is arid and the ground

250-527: A conspicuous shiny black mixture of iron oxides, mostly magnetite with variable amounts of ilmenite and hematite . Valuable mineral components often occurring with black sands are monazite , rutile , zircon , chromite , wolframite , and cassiterite . Early mining operations were probably a result of placer deposits as they were easily accessible and potential size. The events known as gold/diamond rushes were caused by placer deposits and have proved to be plentiful. Placer minerals are defined as having

300-498: 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)

350-527: 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

400-551: A large body of water. Materials collect as beach placers by continuous wave action and currents. Some important examples of beach placers include black sands of Oregon, gold deposits in Nome, Alaska , zircon sands in Brazil and Australia as well as diamond marine gravel in South Africa. Gold bearing beach placers consist of large strips of black sands and are typically constantly changing as

450-403: 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,

500-412: A placer deposit, the particles desired must show a marked density contrast with the gangue material, which is able to be transported away from the trap site. Only if the deposit is winnowed in this way can the minerals be concentrated to economic levels. Beach placers are formed in sand and gravel deposited along the edge of large bodies of water and are typically found where streams or rivers flow into

550-451: 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

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600-968: A result of storms or sporadic wave action. Typically beach placers are populated by ilmenite and magnetite , however gold, platinum and chromite are found in varying amounts. Some of the most productive beach placers are considered ancient beaches that are now far inland from the water, these placers no longer shift with storms and tidal action but with wind and rainfall. Eluvial placers are deposits of metal formed on hillsides and slopes weathered by rainfall and wind. Lighter materials are carried away and weathered leaving concentrations of valuable metals. Eluvial placers are typically not large enough to support large scale mining, however in one case in Nevada there has been large scale gold mining operations based on placer deposits at Round Mountain . Aeolian placers are valuable minerals found in arid regions freed from their source rock by wind actions. Wind erosion leaves

650-471: 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

700-429: 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

750-419: 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

800-413: Is considered an ancient alluvial placer. Substances commercially mined from placer deposits include: Kimberlites are a major source of diamonds. Kimberlites are long "pipes" of lava brought up from the mantle where diamonds form at high temperatures and pressures. These diamonds are then weathered from the source and swept away by alluvial processes (transported by water) to a source that becomes

850-530: Is desired, however substances such as gold typically deform and create irregularly shaped nuggets when subject to mechanical stress. Chemical stability is important for a placer mineral to resist chemical breakdown such as oxidation , Minerals lacking chemical stability will form less desirable alteration when subject to chemical breakdown. Alluvial placers are those formed in river or stream sediments. Another name for alluvial placers are stream placers. Typical locations for alluvial gold placer deposits are on

900-506: 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

950-518: 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

1000-466: Is relatively level leaving wind as the primary erosion force. Paleo-placer deposits are deposits of minerals from all of the above placer types that occurred millions of years ago. These deposits are typically very far underground in ancient riverbeds, beaches, or slopes. The Witwatersrand Basin, South Africa is the largest gold deposit in the world and is considered a paleo-placer, it has produced over 1.5 billion ounces of gold. The Witwatersrand Basin

1050-455: The Aegean Islands (since the sea has a large number of islands). Archipelagos may be found isolated in large amounts of water or neighbouring a large land mass. For example, Scotland has more than 700 islands surrounding its mainland, which form an archipelago. Archipelagos are often volcanic, forming along island arcs generated by subduction zones or hotspots , but may also be

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1100-549: 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

1150-635: The San Juan Islands and Gulf Islands geologically form part of a larger Gulf Archipelago. The word archipelago is derived from the Ancient Greek ἄρχι-( arkhi- , "chief") and πέλαγος ( pélagos , "sea") through the Italian arcipelago . In antiquity , "Archipelago" (from Medieval Greek * ἀρχιπέλαγος and Latin archipelagus ) was the proper name for the Aegean Sea . Later, usage shifted to refer to

1200-453: 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

1250-508: 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

1300-544: 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

1350-648: 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

1400-637: 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

1450-620: 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

1500-559: 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

1550-631: 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

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1600-434: The inside bends of rivers and creeks ; in natural hollows; at the break of slope on a stream; the base of an escarpment , waterfall or other barrier. Stream placers are the most economical and common types of placers and have provided many with riches in the past. Alluvial placers are formed by the deposition of dense particles at a site where water velocity remains below that required to transport them further. To form

1650-512: 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

1700-526: 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

1750-417: 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 ,

1800-450: 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

1850-403: 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

1900-440: 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 ),

1950-526: 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

2000-668: 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

2050-518: The region's economic output. 54°S 70°W  /  54°S 70°W  / -54; -70 Archipelago An archipelago ( / ˌ ɑːr k ə ˈ p ɛ l ə ɡ oʊ / AR -kə- PEL -ə-goh ), sometimes called an island group or island chain , is a chain, cluster, or collection of islands , or sometimes a sea containing a small number of scattered islands. Archipelagos are sometimes defined by political boundaries. For example, while they are geopolitically divided,

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2100-460: The result of erosion , deposition , and land elevation . Depending on their geological origin, islands forming archipelagos can be referred to as oceanic islands , continental fragments , or continental islands . Oceanic islands are mainly of volcanic origin, and widely separated from any adjacent continent. The Hawaiian Islands and Galapagos Islands in the Pacific , and Mascarene Islands in

2150-646: The shelf. The islands of the Inside Passage off the coast of British Columbia and the Canadian Arctic Archipelago are examples. Artificial archipelagos have been created in various countries for different purposes. Palm Islands and The World Islands off Dubai were or are being created for leisure and tourism purposes. Marker Wadden in the Netherlands is being built as a conservation area for birds and other wildlife. The largest archipelago in

2200-432: The south Indian Ocean are examples. Continental fragments correspond to land masses that have separated from a continental mass due to tectonic displacement. The Farallon Islands off the coast of California are an example. Sets of islands formed close to the coast of a continent are considered continental archipelagos when they form part of the same continental shelf, when those islands are above-water extensions of

2250-449: 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

2300-644: 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

2350-537: The world by number of islands is the Archipelago Sea , which is part of Finland . There are approximately 40,000 islands, mostly uninhabited. The largest archipelagic state in the world by area, and by population, is Indonesia . Placer deposit Placer materials must be both dense and resistant to weathering processes. To accumulate in placers, mineral particles must have a specific gravity above 2.58. Placer environments typically contain black sand ,

2400-502: 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

2450-593: 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

2500-472: 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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