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81-591: The volcano is andesitic in nature, and the current pattern of activity includes periods of lava dome growth, punctuated by brief episodes of dome collapse which result in pyroclastic flows , ash venting, and explosive eruption. The volcano is monitored by the Montserrat Volcano Observatory . Volcanic gas emissions from this volcano are measured by a multi-component gas analyzer system , which detects pre-eruptive degassing of rising magmas, improving prediction of volcanic activity . The Centre Hills in

162-547: A citizenship by investment program. The country levies no personal income tax . Antigua is Spanish for 'ancient' and barbuda is Spanish for 'bearded'. The island of Antigua was originally called Wadadli by the Arawaks and is locally known by that name today; the Caribs possibly called Barbuda Wa'omoni . Christopher Columbus , while sailing by in 1493, may have named it Santa Maria la Antigua , after an icon in

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

324-584: A degree of political stability, and boosting tourism to the country, the Bird governments were frequently accused of corruption, cronyism and financial malfeasance. Vere Bird Jr. , the elder son, was forced to leave the cabinet in 1990 following a scandal in which he was accused of smuggling Israeli weapons to Colombian drug-traffickers. Another son, Ivor Bird , was convicted of selling cocaine in 1995. In 1995, Hurricane Luis caused severe damage on Barbuda. The ABLP's dominance of Antiguan politics ended with

405-539: A major role in evacuating Montserrat's population to other islands, including Antigua and Barbuda who warned they would not be able to cope with many more refugees. About 7,000 people, or two-thirds of the population, left Montserrat; 4,000 went to the United Kingdom. The following is a list of Montserrat settlements abandoned by the eruption of the Soufrière Hills volcano: †Settlement was destroyed In addition,

486-855: A new mechanism to generate andesite crust. Along with basalts, andesites are a component of the Martian crust . The presence of distinctive steep-sided domes on Venus suggests that andesite may have been erupted from large magma chambers where crystal settling could take place. Volcanic rocks : Subvolcanic rocks : Plutonic rocks : Picrite basalt Peridotite Basalt Diabase (Dolerite) Gabbro Andesite Microdiorite Diorite Dacite Microgranodiorite Granodiorite Rhyolite Microgranite Granite Antigua and Barbuda Antigua and Barbuda ( UK : / æ n ˈ t iː ɡ ə  ...   b ɑːr ˈ b uː d ə / , US : / æ n ˈ t iː ɡ w ə  ...   b ɑːr ˈ b j uː d ə / )

567-549: A small number of East Asians and Sephardic Jews make up the remainder of the population. An increasingly large percentage of the population lives abroad, most notably in the United Kingdom ( Antiguan Britons ), the United States and Canada. A minority of Antiguan residents are immigrants from other countries, particularly from Dominica, Guyana and Jamaica , and, increasingly, from the Dominican Republic, St. Vincent and

648-518: 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

729-471: A thick layer of ash and darkened the sky almost completely. Pyroclastic flows were first observed on 27 March 1996. Although these pyroclastic flows and mudflows were initially confined to unpopulated areas, a major pyroclastic flow on 17 September 1996 caused severe damage to the village of Long Ground, near the volcano. By August 1997, much of the southern part of the island, including most of Plymouth, had been buried by pyroclastic flows. During this period,

810-400: Is Codrington . It is estimated that 25% of the population lives in an urban area, which is much lower than the international average of 55%. Antigua and Barbuda consists mostly of its two namesake islands, Antigua , and Barbuda . Other than that, Antigua and Barbuda's biggest islands are Guiana Island and Long Island off the coast of Antigua, and Redonda island, which is far from both of

891-469: Is a constitutional monarchy with Charles III as its head of state. The economy of Antigua and Barbuda is largely dependent on tourism, which accounts for 80% of its GDP. Like other island nations , Antigua and Barbuda is vulnerable to the effects of climate change , such as sea level rise , and increased intensity of extreme weather like hurricanes . These cause coastal erosion , water scarcity , and other challenges. Antigua and Barbuda offers

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972-744: Is a sovereign archipelagic country in the Caribbean . It lies at the conjuncture of the Caribbean Sea and the Atlantic Ocean in the Leeward Islands part of the Lesser Antilles . The country consists of two major islands, Antigua and Barbuda , which are approximately 40 km (25 mi) apart, and several smaller islands, including Great Bird , Green , Guiana , Long , Maiden , Prickly Pear , York , and Redonda . The permanent population

1053-472: Is a unitary parliamentary democracy under a constitutional monarchy . The current Constitution of Antigua and Barbuda was adopted upon independence on 1 November 1981. This replaced the pre-independence constitution of the Associated State of Antigua , which did not thoroughly define the relationship between the two islands. The island of Barbuda maintains much autonomy, while the island of Antigua

1134-435: 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 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

1215-499: Is a small, uninhabited island located about 40 kilometres (25 miles) to the south-west of Antigua. Redonda is a rocky island. In Antigua and Barbuda forest cover is about 18% of the total land area, equivalent to 8,120 ha of forests in 2020, down from 10,110 ha in 1990. The most populous cities in Antigua and Barbuda are mostly on Antigua, being Saint John's , All Saints , Piggotts , and Liberta . The most populous city on Barbuda

1296-519: Is approximately 97,120 (2019 estimates), with 97% residing in Antigua. St. John's , Antigua, is the country's capital, major city, and largest port. Codrington is Barbuda's largest town. In 1493, Christopher Columbus surveyed the island of Antigua, which he named for the Church of Santa María La Antigua . Great Britain colonized Antigua in 1632 and Barbuda in 1678. A part of the Federal Colony of

1377-582: Is completely inactive, except for the Barbuda Council which is enshrined in the Constitution. Antigua historically had a system of village councils in the 1940s (although the legislation was never repealed), however, the Gaston Browne administration has expressed opposition to all forms of local governance. St. John's also historically had a city council during the late 1800s and early 1900s, however

1458-583: Is directly governed by the national government. The executive branch has two primary leaders. The Governor-General , currently Rodney Williams , exercises the functions of the Monarch of Antigua and Barbuda , in whom executive power is vested in. The Governor-General serves at the pleasure of the Monarch, and usually serves a similar term to that of the Prime Minister . The Prime Minister, currently Gaston Browne ,

1539-462: 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 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

1620-533: 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 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

1701-723: Is responsible for the national security of Antigua and Barbuda . The Defence Force consists of the Regiment (army), the Air Wing , the Coast Guard , and the Service and Support Battalion. The Defence Force is led by the Chief of Defence Staff, who is subject to the orders of the Governor-General. The Defence Force is headquartered at Camp Blizzard . The National Security Council is responsible for

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1782-514: 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

1863-554: Is the head of government , and is appointed by the Governor-General. The Prime Minister must be a member of the House of Representatives , and must be the member of the House of Representatives who is most likely to command the support of the majority of members. The Governor-General has the ability to dissolve Parliament on the advice of the Prime Minister, or when the majority of the members of

1944-542: Is the highest point on both Antigua and Barbuda. It is the remnant of a volcanic crater and rises a total of 402 meters. Boggy Peak is located in the southwest of Antigua (1,319 feet). Both of these islands have very irregularly shaped coastlines that are dotted with beaches, lagoons, and natural harbours. There are reefs and shoals that surround the islands on all sides. Because of the low amount of rainfall, there are not many streams. On neither of these islands can sufficient quantities of fresh groundwater be found. Redonda

2025-433: 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

2106-447: 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 is usually porphyritic , containing larger crystals ( phenocrysts ) of plagioclase formed prior to

2187-615: The 2004 Antiguan general election , which was won by Winston Baldwin Spencer 's United Progressive Party (UPP). Winston Baldwin Spencer was Prime Minister of Antigua and Barbuda from 2004 to 2014. However the UPP lost the 2014 Antiguan general election , with the ABLP returning to power under Gaston Browne . ABLP won 15 of the 17 seats in the 2018 snap election under the leadership of incumbent Prime Minister Gaston Browne. In 2016, Nelson's Dockyard

2268-500: 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

2349-582: The Antigua and Barbuda Labour Party (ABLP) (Premier from 1967 to 1971 and 1976 to 1981) and the Progressive Labour Movement (PLM) of George Walter (Premier 1971–1976). Eventually, Antigua and Barbuda gained full independence on 1 November 1981; Vere Bird became prime minister of the new country. The country opted to remain within the Commonwealth , retaining Queen Elizabeth as head of state , with

2430-935: The Caribbean Community , the Alliance of Small Island States , and the World Trade Organization . Antigua and Barbuda's foreign policy has been described by Gaston Browne as "we are friends of all; enemies of none". Antigua and Barbuda has rejected the notion that it is in any country's "backyard". Antigua and Barbuda usually maintains close relations with other Small Island Developing States , and has hosted various summits on that subject. The United Nations has also praised Antigua and Barbuda for its "United Nations-based multilateralism" efforts. Antigua and Barbuda also has close relations with many Caribbean countries and territories, especially Montserrat , which Antigua and Barbuda accepted 3,000 refugees from in 1997 after

2511-732: The Progressive Labour Movement government (predecessor of the UPP) from 1971 to 1976, and the United Progressive Party government from 2004 until 2014. On Barbuda, dominant party is traditionally the Barbuda People's Movement , being the only political grouping in the Barbuda Council since 2023 . Antigua and Barbuda is composed of six parishes and two dependencies . Saint John is the most populous parish, home to well over half of Antigua and Barbuda's population. During colonial times,

Soufrière Hills - Misplaced Pages Continue

2592-580: The Soufrière Hills eruption. Many policies adopted by the Antiguan and Barbudan government have also often had an impact on Montserrat, due to Antigua and Barbuda hosting the only air and transportation links into the territory. The Minister of Finance, Corporate Governance & Public Private Partnerships is responsible for the Antigua and Barbuda Defence Force , the country's military. The Minister of Legal Affairs, Public Safety, Immigration and Labour

2673-838: The Supreme Court including the High Court and the Court of Appeal, and finally the Judicial Committee of the Privy Council , the country's final court. Antiguan and Barbudan voters rejected a proposal to make the Caribbean Court of Justice the final court in 2018. Antigua and Barbuda is composed of three magistrates' courts districts, and is part of the Eastern Caribbean Supreme Court system. The acting chief justice of

2754-502: The W. H. Bramble Airport was destroyed. On 24 December 2006, streaks of red from the pyroclastic flows became visible. On 8 January 2007, an evacuation order was issued for areas in the Lower Belham Valley, affecting an additional 100 people. At 11:27 pm local time on Monday 28 July 2008, an eruption began without any precursory activity. Pyroclastic flow lobes reached Plymouth. These involved juvenile material originating in

2835-612: The lava dome sent large ash clouds over sections of several nearby islands, including Guadeloupe and Antigua . Inhabited areas of Montserrat itself received very little ash accumulation during either event. On 12 February 2010, at 1200 UTC/GMT, Meteosat SEVIRI Channel 7 shows the ash plume from the eruption was caught up within the warm sector of a frontal system heading towards western Europe exacerbating two East Atlantic winter storms. [reference] Violent storms accompanied by torrential rain and high wind passed over Madeira on 20 February and western Europe on 26-28 February. In Madeira there

2916-442: 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,

2997-553: The Barbudan one. When compared to Antiguan Creole , Standard English was the language of choice in the years leading up to Antigua and Barbuda's attainment of their independence. The Antiguan Creole language is looked down upon by the upper and middle classes in general. The Antiguan Creole language is discouraged from use in the educational system, and instruction is carried out in Standard (British) English instead. A significant number of

3078-532: The Grenadines and Nigeria . An estimated 4,500 American citizens also make their home in Antigua and Barbuda, making their numbers one of the largest American populations in the English-speaking Eastern Caribbean. 68.47% of the population was born in Antigua and Barbuda. The language most commonly used in business is English . There is a noticeable distinction between the Antiguan accent and

3159-534: The House of Representatives as an ex officio member. The Attorney-General also attends sittings of the Senate. Any bill except money bills may be introduced in either chamber: money bills may only be introduced in the House. Parliament may not amend the Barbuda Local Government Act without the consent of the Barbuda Council. The judiciary of Antigua and Barbuda is composed of the magistrates' courts,

3240-525: The House of Representatives pass a motion of no confidence, and the Prime Minister does not within seven days resign or advise the Governor-General to dissolve Parliament. The legislative power of Antigua and Barbuda is vested in Parliament, which is composed of the Monarch, the Senate , and the House of Representatives . The Senate is composed of seventeen members, who are appointed by the Governor-General. Ten of

3321-602: The Leeward Islands from 1871, Antigua and Barbuda joined the West Indies Federation in 1958. With the breakup of the federation in 1962, it became one of the West Indies Associated States in 1967. Following a period of internal self-governance, it gained full independence from the United Kingdom on 1 November 1981. Antigua and Barbuda is a member of the Commonwealth and a Commonwealth realm ; it

Soufrière Hills - Misplaced Pages Continue

3402-575: The Montserrat population; however, riots followed as the people protested that the British Government was not doing enough for aid relief. The riots followed a £10 million aid offer by International Development Secretary Clare Short , prompting the resignation of Bertrand Osborne , then Chief Minister of Montserrat , after allegations that he was too pro-British and had not demanded a better offer. The British destroyer HMS  Liverpool took

3483-570: The Spanish Seville Cathedral . The "bearded" of Barbuda is thought to refer either to the male inhabitants of the island, or the bearded fig trees present there. Antigua was first settled by archaic age Indigenous hunter-gatherers called the Ciboney . Carbon dating has established the earliest settlements started around 3100 BC. They were succeeded by the ceramic age pre-Columbian Arawak -speaking Saladoid people who migrated from

3564-561: The St. John's Development Corporation has since consumed most of its functions. The Minister of Foreign Affairs, Trade & Barbuda Affairs is responsible for overseeing the foreign relations of Antigua and Barbuda. The current minister is Paul Chet Greene . Antigua and Barbuda is a founding member of the Organisation of Eastern Caribbean States , as well as a member of the United Nations ,

3645-482: The Supreme Court is Mario Michel , serving since 5 May 2024. Since the 1990s, the two major parties in Antigua have been the centre-right (formerly left-wing) Antigua and Barbuda Labour Party , and the left-wing social democratic United Progressive Party . The Labour Party and its predecessors have traditionally been the dominant party on the national level since the 1946 general elections , with brief pauses during

3726-469: The advice of the Barbuda Council , and an independent senator is appointed under the discretion of the Governor-General himself. The House of Representatives is currently composed of seventeen elected members, as well as the Speaker of the House , who is elected by the members of the House itself. The Attorney General , while currently an elected member of Parliament, Steadroy Benjamin , may also be appointed to

3807-824: The ages of 5 and 16 years. The system is modeled on the British educational system. The current Minister of Education, Sport & Creative Industries is Daryll Sylvester Matthew . The adult literacy rate in Antigua and Barbuda is approximately 99%. A majority (77%) of Antiguans are Christians, with the Anglicans (17.6%) being the largest single denomination. Other Christian denominations present are Seventh-day Adventist Church (12.4%), Pentecostalism (12.2%), Moravian Church (8.3%), Roman Catholics (8.2%), Methodist Church (5.6%), Wesleyan Holiness Church (4.5%), Church of God (4.1%), Baptists (3.6%), Mormonism (<1.0%), as well as Jehovah's Witnesses . Antigua and Barbuda

3888-408: 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,

3969-624: The central part of the island and the Silver Hills in the north are older volcanic massifs related to the subduction zone. There are three main parts of the island: the central zone, subduction and exclusion. Many volcanoes in the Caribbean are named Soufrière ( French : " sulphur outlet"). These include La Soufrière or Soufrière Saint Vincent on the island of Saint Vincent , and La Grande Soufrière on Guadeloupe . Seismic activity had occurred in 1897–1898, 1933–1937, and again in 1966–1967, but

4050-472: The collapse of the eruption column. In addition, a small part of the eastern side of the lava dome collapsed, generating a pyroclastic flow in Tar River Valley. Several large explosions were registered, with the largest at approximately 11:38 pm. The height of the ash column was estimated at 12,000 m (40,000 ft) above sea level. The volcano has become one of the most closely monitored volcanoes in

4131-446: The dominant rock type in island arcs . The average composition of the continental crust is andesitic. Along with basalts, andesites are 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

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4212-642: The eruption that began on 18 July 1995 was the first since the turn of the 20th century. The first phreatic explosion in this new period of activity occurred on 21 August 1995, and such activity lasted for 18 weeks until it caused an andesitic lava dome formation. This was initially confined by a sector-collapse scar, first identified in the 1930's and called English's Crater . This period of activity lasted for another 60 weeks, after which there were major dome collapses and two periods of explosive volcanic eruptions and fountain-collapse pyroclastic flows. The explosion blanketed Plymouth, 6 kilometres (3.7 mi) away, in

4293-431: 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 the most abundant phenocryst . For example, if hornblende

4374-511: The first governor , Sir Wilfred Jacobs , as governor-general . Succeeding Sir Wilfred Jacobs were Sir James Carlisle (June 10, 1993 – June 30, 2007), Dame Louise Lake-Tack (July 17, 2007 – August 14, 2014.), and the present governor, Sir Rodney Williams: (August 14, 2014 – present). The first two decades of Antigua's independence were dominated politically by the Bird family and the ABLP, with Vere Bird ruling from 1981 to 1994, followed by his son Lester Bird from 1994 to 2004. Though providing

4455-521: The following rebuilding efforts on Barbuda that were estimated to cost at least $ 100 million, the government announced plans to revoke a century-old law of communal land ownership by allowing residents to buy land; a move that has been criticised as promoting " disaster capitalism ". Limestone formations, rather than volcanic activity, have had the most impact on the topography of both Antigua and Barbuda, which are both relatively low-lying islands. Boggy Peak, also known as Mt. Obama from 2008 to 2016,

4536-624: The island are further made worse by climate change , where, not unlike other island nations affected by climate change , sea level rise and increased weather variability, create increased pressures on the communities on the islands and the land, through processes like coastal erosion and saltwater intrusion . Antigua has a population of 93,219, mostly made up of people of West African , British, and Portuguese descent. The ethnic distribution consists of 91% Black, 4.4% mixed race, 1.7% White, and 2.9% other (primarily East Indian ). Most Whites are of British descent. Christian Levantine Arabs and

4617-415: The island has since remained uninhabited. Part of the Leeward Islands colony, Antigua and Barbuda became part of the short-lived West Indies Federation from 1958 to 1962. Antigua and Barbuda subsequently became an associated state of the United Kingdom with full internal autonomy on 27 February 1967. The 1970s were dominated by discussions as to the islands' future and the rivalry between Vere Bird of

4698-486: The lower Orinoco River . They introduced agriculture, raising, among other crops, the famous Antigua Black Pineapple ( Ananas comosus ), corn , sweet potatoes , chiles , guava , tobacco, and cotton. Later on the Caribs settled the island. Christopher Columbus was the first European to sight the islands in 1493. The Spanish did not colonise Antigua until after a combination of European and African diseases, malnutrition, and slavery eventually extirpated most of

4779-462: The main islands. Rainfall averages 990 mm (39 in) per year, with the amount varying widely from season to season. In general the wettest period is between September and November. The islands generally experience low humidity and recurrent droughts. Temperatures average 27 °C (80.6 °F), with a range from 23 °C (73.4 °F) to 29 °C (84.2 °F) in the winter to from 25 °C (77.0 °F) to 30 °C (86.0 °F) in

4860-437: 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

4941-506: The members are appointed on the advice of the Prime Minister, these members being known as government senators. An eleventh government senator is also appointed on the advice of the Prime Minister, who must be an inhabitant of Barbuda. Four of the members are appointed on the advice of the Leader of the Opposition , these senators being known as opposition senators. One of the members is appointed on

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5022-588: The mineral composition of volcanic rocks, due to their very fine grain size, and andesite is then defined chemically as volcanic rock with 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

5103-512: 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

5184-506: The native population; smallpox was probably the greatest killer. The English settled on Antigua in 1632; Christopher Codrington settled on Barbuda in 1685. Tobacco and then sugar was grown, worked by a large population of slaves transported from West Africa, who soon came to vastly outnumber the European settlers. The English maintained control of the islands, repulsing an attempted French attack in 1666. The brutal conditions endured by

5265-481: The northwest. A large eruption on 25 June 1997 resulted in the deaths of nineteen people. The island's airport was directly in the path of the main pyroclastic flow and was completely destroyed. Montserrat's tourist industry also collapsed, although it began partially to recover within fifteen years. The governments of the United Kingdom and Montserrat led the aid effort, including a £41 million package provided to

5346-510: 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

5427-441: 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

5508-544: The parishes were governed by parish vestries, however, the parishes now lack any sort of government. Since the 2023 general elections, various proposals have been made to establish parish councils, however, as of June 2024, none have been established. The dependency of Redonda is part of the parish of Saint John under the Redonda Annexation Act, in Magistrates' District "A". Local government in Antigua and Barbuda

5589-502: The situation as follows: "Public utilities need to be rebuilt in their entirety... It is optimistic to think anything can be rebuilt in six months ... In my 25 years in disaster management, I have never seen something like this." Like other island nations , Antigua and Barbuda faces unique environmental issues created by its proximity to the ocean, and small size. These include pressures on drinking water resources, natural ecosystems, and deforestation more generally. Existing issues on

5670-488: The slaves led to revolts in 1701 and 1729 and a planned revolt in 1736, the last led by Prince Klaas , though it was discovered before it began and the ringleaders were executed. Slavery was abolished in the British Empire in 1833, affecting the economy. This was exacerbated by natural disasters such as the 1843 earthquake and the 1847 hurricane. Mining occurred on the isle of Redonda , however, this ceased in 1929 and

5751-411: The southern portion of the island, including the capital Plymouth, was evacuated three times. The first evacuation lasted from 21 August 1995 - 3 September 1995, after the first phreatic eruption. The second evacuation began on 1 December 1995, due to growth of the lava dome. Residents were allowed back to most areas, including Plymouth, on 1 January 1996, but residents of some areas on the eastern flank of

5832-671: The summer and autumn. The coolest period is between December and February. Hurricanes strike on an average of once a year, including the powerful Category 5 Hurricane Irma , on 6 September 2017, which damaged 95% of the structures on Barbuda. Some 1,800 people were evacuated to Antigua. Officials quoted by Time indicated that over $ 100 million would be required to rebuild homes and infrastructure. Philmore Mullin, Director of Barbuda's National Office of Disaster Services, said that "all critical infrastructure and utilities are non-existent – food supply, medicine, shelter, electricity, water, communications, waste management". He summarised

5913-411: The surface of the volcano on Montserrat – one six kilometres below the surface and the other 12 kilometres (7.5 mi) below the surface. The journal also showed a link between surface behaviour and the size of the deeper magma chamber. On 5 February 2010, a vulcanian explosion simultaneously propelled pyroclastic flows down several sides of the mountain, and on 11 February 2010, a partial collapse of

5994-541: 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

6075-585: 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 ,

6156-423: The volcano were not allowed back until 15 January 1996. On 3 April 1996, after pyroclastic flows and mudflows began occurring regularly, southern Montserrat, including the capital, Plymouth, was permanently evacuated. Earthquakes continued to occur in three epicentre zones: beneath the Soufrière Hills volcano, in the ridge running to the northeast, and beneath St George's Hill, about 5 kilometres (3.1 mi) to

6237-481: 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

6318-476: The words that are used in the Antiguan dialect are derived from both the British and African languages. This is readily apparent in phrases such as "Innit?" which literally translates to "Isn't it?" Many common island proverbs can be traced back to Africa, such as the pidgin language. Approximately 10,000 people are able to speak in Spanish. Education in Antigua and Barbuda is compulsory and free for children between

6399-480: The world since its eruption began, with the Montserrat Volcano Observatory taking detailed measurements and reporting on its activity to the government and population of Montserrat. The observatory is operated by the British Geological Survey , under contract to the government of Montserrat. The 9 October 2008 issue of the journal Science suggested that two interconnected magma chambers lie beneath

6480-424: Was at least 48 fatalities and damage to infrastructure at a total estimated cost of 4 billion Euros. The storm landfalling in western France (named 'Cyclone Xynthia') resulted in at least 63 fatalities and estimated damage within the range of 1.3-3 billion Euros. Yim, W. 2016. Volcanoes and disastrous storms. Imperial Engineer, Spring 2016, p. 19. Andesitic Andesite ( / ˈ æ n d ə z aɪ t / )

6561-422: Was designated as a UNESCO World Heritage Site . Most of Barbuda was devastated in early September 2017 by Hurricane Irma , which brought winds with speeds reaching 295 km/h (185 mph). The storm damaged or destroyed 95% of the island's buildings and infrastructure, leaving Barbuda "barely habitable" according to Prime Minister Gaston Browne. Nearly everyone on the island was evacuated to Antigua. Amidst

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