Soufrière Hills
Encyclopedia
The Soufrière Hills volcano (French
French language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

 Sulphur Hills) is an active complex stratovolcano
Stratovolcano
A stratovolcano, also known as a composite volcano, is a tall, conical volcano built up by many layers of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic, explosive eruptions...

 with many lava domes forming its summit on the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...

 island of Montserrat
Montserrat
Montserrat is a British overseas territory located in the Leeward Islands, part of the chain of islands called the Lesser Antilles in the West Indies. This island measures approximately long and wide, giving of coastline...

. After a long period of dormancy, it became active in 1995, and has continued to erupt ever since. Its eruptions have rendered more than half of Montserrat uninhabitable, destroying the capital city, Plymouth
Plymouth, Montserrat
Plymouth is the de jure capital of the island of Montserrat, an overseas territory of the United Kingdom located in the Leeward Island chain of the Lesser Antilles, West Indies. The town was overwhelmed by volcanic eruptions starting in the 1990s and was abandoned...

, and causing widespread evacuations: about two thirds of the population left the island.

The volcano is andesitic in nature and the current pattern of activity includes periods of dome
Lava dome
|250px|thumb|right|Image of the [[rhyolitic]] lava dome of [[Chaitén Volcano]] during its 2008–2009 eruption.In volcanology, a lava dome is a roughly circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano...

 growth, punctuated by brief episodes of dome collapse which result in pyroclastic flows, ash venting, and explosive eruption.

1995–1999

Seismic activity had occurred in 1897–1898, 1933–1937, and again in 1966–1967, but the eruption that began on 18 July 1995 was the first since the 19th century in Montserrat. When pyroclastic flow
Pyroclastic flow
A pyroclastic flow is a fast-moving current of superheated gas and rock , which reaches speeds moving away from a volcano of up to 700 km/h . The flows normally hug the ground and travel downhill, or spread laterally under gravity...

s and mudflows began occurring regularly, Plymouth was evacuated, and a few weeks later a pyroclastic flow covered the city in several metres of debris. 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. This was initially confined by a sector-collapse scar. This period lasted for another 60 weeks, after which there were major dome collapses and two periods of explosive Vulcanian eruptions and fountain-collapse pyroclastic flows. It blanketed Plymouth, 6 kilometres (3.7 mi) away in a thick layer of ash and darkened the sky almost completely. Earthquakes continue to occur in three epicentral zones: beneath the Soufrière Hills volcano itself, in the ridge running to the north-east and beneath St George's Hill, about 5 kilometres (3.1 mi) to the north-west. 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 was also destroyed. However, it is now regenerating.

The governments of the United Kingdom
Politics of the United Kingdom
The politics of the United Kingdom takes place within the framework of a constitutional monarchy, in which the Monarch is the head of state and the Prime Minister of the United Kingdom is the head of government...

 and Montserrat led the aid effort, including a £41 million package provided to the people of Montserrat; however, riots followed as the people protested that the British Government was not doing enough to aid relief. This had followed at £10 million aid offer by International Development Secretary Claire Short, prompting the resignation of Bertrand Osborne
Bertrand Osborne
Bertrand Osborne is a politician from Montserrat. He served as the territory's Chief Minister from 13 November 1996 to 22 August 1997. He resigned from his post amid demonstrations over his dealings with the British government in the wake of the island nation being ravaged by a volcano...

, then Chief Minister of Montserrat
Chief Minister of Montserrat
The Chief Minister of Montserrat is the head of government of Montserrat, an island in the Caribbean that is an overseas territory of the United Kingdom, appointed by the Governor of Montserrat on behalf of Queen Elizabeth II, Montserrat's head of state. The current Chief Minister of Montserrat is...

 after allegations of being too pro-British and not demanding a better offer. The British destroyer
Destroyer
In naval terminology, a destroyer is a fast and maneuverable yet long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller, powerful, short-range attackers. Destroyers, originally called torpedo-boat destroyers in 1892, evolved from...

 HMS Liverpool
HMS Liverpool (D92)
HMS Liverpool is a Type 42 destroyer of the Royal Navy. She was built by Cammell Laird in Birkenhead and launched on 25 September 1980 by Lady Strathcona, wife of Euan Howard, the then Minister of State for Defence. Liverpool is the last Batch 2 Type 42 in service.-Operational history:Liverpool was...

took a large role in evacuating Montserrat's population to other islands; this included Antigua and Barbuda
Antigua and Barbuda
Antigua and Barbuda is a twin-island nation lying between the Caribbean Sea and the Atlantic Ocean. It consists of two major inhabited islands, Antigua and Barbuda, and a number of smaller islands...

, 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 to the United Kingdom.

Since 1999

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 the collapse of the eruption column. Further, 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 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
British Geological Survey
The British Geological Survey is a partly publicly funded body which aims to advance geoscientific knowledge of the United Kingdom landmass and its continental shelf by means of systematic surveying, monitoring and research. The BGS headquarters are in Keyworth, Nottinghamshire, but other centres...

 under contract to the government of Montserrat.

The 9 October 2008 issue of the journal Science
Science (journal)
Science is the academic journal of the American Association for the Advancement of Science and is one of the world's top scientific journals....

suggests that two interconnected magma chambers lie beneath the surface of the volcano on Montserrat – one six kilometers below the surface and the other at 12 kilometers below the surface. They also show a link between surface behavior and the size of the deeper magma chamber.

On 5 February 2010, a vulcanian explosion
Vulcanian eruption
The term Vulcanian was first used by Giuseppe Mercalli, witnessing the 1888-1890 eruptions on the island of Vulcano. His description of the eruption style is now used all over the world for eruptions characterised by a dense cloud of ash-laden gas exploding from the crater and rising high above the...

 simultaneously propelled pyroclastic flows down several sides of the mountain, and on 11 February 2010, a partial collapse of the lava dome sent large ash clouds over sections of several nearby islands including Guadeloupe
Guadeloupe
Guadeloupe is an archipelago located in the Leeward Islands, in the Lesser Antilles, with a land area of 1,628 square kilometres and a population of 400,000. It is the first overseas region of France, consisting of a single overseas department. As with the other overseas departments, Guadeloupe...

 and Antigua
Antigua
Antigua , also known as Waladli, is an island in the West Indies, in the Leeward Islands in the Caribbean region, the main island of the country of Antigua and Barbuda. Antigua means "ancient" in Spanish and was named by Christopher Columbus after an icon in Seville Cathedral, Santa Maria de la...

. Inhabited areas of Montserrat itself received very little ash accumulation through either event.

In popular culture

Soufrière Hills is the namesake of the Jimmy Buffett
Jimmy Buffett
James William "Jimmy" Buffett is a singer-songwriter, author, entrepreneur, and film producer. He is best known for his music, which often portrays an "island escapism" lifestyle. Together with his Coral Reefer Band, Buffett's musical hits include "Margaritaville" , and "Come Monday"...

 song "Volcano
Volcano (Jimmy Buffett song)
"Volcano" is a song performed by American popular music singer-songwriter Jimmy Buffett. It was written by Jimmy Buffett, Keith Sykes, and Harry Dailey and released as a single on MCA 41161 in November 1979....

".

See also


External links

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