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72-594: It is located on Saint Kitts island , near the point of the Southeast Peninsula and to the north of The Narrows isthmus. St. Anthony's Peak overlooks it. It is a wildlife habitat for: birds , such as the common gallinule and the great blue heron ; invertebrates ; and fish , including as an estuary nursery area for Caribbean Sea dwelling fish. 17°14′N 62°39′W  /  17.233°N 62.650°W  / 17.233; -62.650 This Saint Kitts and Nevis location article

144-886: A mid-ocean ridge , such as the Mid-Atlantic Ridge , has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift , the Wells Gray-Clearwater volcanic field , and the Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from

216-437: A graduated spectrum, with much overlap between categories, and does not always fit neatly into only one of these three separate categories. The USGS defines a volcano as "erupting" whenever the ejection of magma from any point on the volcano is visible, including visible magma still contained within the walls of the summit crater. While there is no international consensus among volcanologists on how to define an active volcano,

288-508: A growth of just under 40% in a two-year period. As tourism grows, the demand for vacation property increases in conjunction. Saint Kitts & Nevis also acquires foreign direct investment from their unique citizenship-by-investment programme, outlined in their Citizenship Act of 1984. Interested parties can acquire citizenship if they pass the government's strict background checks and make an investment into an approved real estate development. Purchasers who pass government due diligence and make

360-589: A minimum investment of US$ 400,000, into qualifying government-approved real estate, are entitled to apply for citizenship of the Federation of Saint Kitts and Nevis. Many projects are approved under the citizenship-by-investment programme. The country hosts an annual St. Kitts Music Festival . Robert L. Bradshaw International Airport serves Saint Kitts. The Basseterre Ferry Terminal facilitates travel between Saint Kitts and sister island Nevis. The narrow-gauge (30 inches ) St. Kitts Scenic Railway circles

432-443: A paper was published suggesting a new definition for the word 'volcano' that includes processes such as cryovolcanism . It suggested that a volcano be defined as 'an opening on a planet or moon's surface from which magma , as defined for that body, and/or magmatic gas is erupted.' This article mainly covers volcanoes on Earth. See § Volcanoes on other celestial bodies and cryovolcano for more information. The word volcano

504-686: A shallow 3-kilometre (2 mi) channel known as " The Narrows ". Saint Kitts became home to the first Caribbean British and French colonies in the mid-1620s. Along with the island of Nevis, Saint Kitts was a member of the British West Indies until gaining independence on 19 September 1983. The island is one of the Leeward Islands in the Lesser Antilles . It is situated about 2,100 km (1,300 mi) southeast of Miami , Florida , US. The land area of Saint Kitts

576-632: A volcano is largely determined by the composition of the lava it erupts. The viscosity (how fluid the lava is) and the amount of dissolved gas are the most important characteristics of magma, and both are largely determined by the amount of silica in the magma. Magma rich in silica is much more viscous than silica-poor magma, and silica-rich magma also tends to contain more dissolved gases. Lava can be broadly classified into four different compositions: Mafic lava flows show two varieties of surface texture: ʻAʻa (pronounced [ˈʔaʔa] ) and pāhoehoe ( [paːˈho.eˈho.e] ), both Hawaiian words. ʻAʻa

648-555: A volcano is of a conical mountain, spewing lava and poisonous gases from a crater at its summit; however, this describes just one of the many types of volcano. The features of volcanoes are varied. The structure and behaviour of volcanoes depend on several factors. Some volcanoes have rugged peaks formed by lava domes rather than a summit crater while others have landscape features such as massive plateaus . Vents that issue volcanic material (including lava and ash ) and gases (mainly steam and magmatic gases) can develop anywhere on

720-465: A volcano that has experienced one or more eruptions that produced over 1,000 cubic kilometres (240 cu mi) of volcanic deposits in a single explosive event. Such eruptions occur when a very large magma chamber full of gas-rich, silicic magma is emptied in a catastrophic caldera -forming eruption. Ash flow tuffs emplaced by such eruptions are the only volcanic product with volumes rivalling those of flood basalts . Supervolcano eruptions, while

792-517: Is Mount Liamuiga, formerly Mount Misery, a dormant volcano 1,156 metres (3,793 ft) high. The youngest volcanic centre is Mt. Liamuiga , 5 kilometres (3.1 mi) in diameter and rising to an elevation of 1,155 metres (3,789 ft). Its last eruption was 1,620 years ago, corresponding with the Steel Dust series of pyroclastic deposits on the western flank. The Mansion Series of pyroclastic deposits and andesite with basalt layers occur on

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864-612: Is a stub . You can help Misplaced Pages by expanding it . Saint Kitts Saint Kitts , officially Saint Christopher , is an island in the West Indies . The west side of the island borders the Caribbean Sea, and the eastern coast faces the Atlantic Ocean . Saint Kitts and the neighbouring island of Nevis constitute one country: the Federation of Saint Kitts and Nevis . Saint Kitts and Nevis are separated by

936-739: Is a volcanic field of over 60 cinder cones. Based on satellite images, it has been suggested that cinder cones might occur on other terrestrial bodies in the Solar system too; on the surface of Mars and the Moon. Stratovolcanoes (composite volcanoes) are tall conical mountains composed of lava flows and tephra in alternate layers, the strata that gives rise to the name. They are also known as composite volcanoes because they are created from multiple structures during different kinds of eruptions. Classic examples include Mount Fuji in Japan, Mayon Volcano in

1008-507: Is about 168 km (65 sq mi), being approximately 29 km (18 mi) long and on average about 8 km (5.0 mi) across. Saint Kitts has a population of about 40,000, the majority of whom are of African descent . The primary language is English , with a literacy rate of approximately 98%. Residents call themselves Kittitians . The island is named after the Christian Saint Christopher ; "Kit"

1080-472: Is also home to several institutions of higher education, including Ross University School of Veterinary Medicine , Windsor University School of Medicine , and the University of Medicine and Health Sciences . The capital of the two-island nation, and also its largest port, is the town of Basseterre on Saint Kitts. There is a modern facility for handling large cruise ships there. A ring road goes around

1152-412: Is characterized by a rough, clinkery surface and is the typical texture of cooler basalt lava flows. Pāhoehoe is characterized by its smooth and often ropey or wrinkly surface and is generally formed from more fluid lava flows. Pāhoehoe flows are sometimes observed to transition to ʻaʻa flows as they move away from the vent, but never the reverse. More silicic lava flows take the form of block lava, where

1224-565: Is derived from the name of Vulcano , a volcanic island in the Aeolian Islands of Italy whose name in turn comes from Vulcan , the god of fire in Roman mythology . The study of volcanoes is called volcanology , sometimes spelled vulcanology . According to the theory of plate tectonics, Earth's lithosphere , its rigid outer shell, is broken into sixteen larger and several smaller plates. These are in slow motion, due to convection in

1296-584: Is expressed using the volcanic explosivity index (VEI), which ranges from 0 for Hawaiian-type eruptions to 8 for supervolcanic eruptions. As of December 2022 , the Smithsonian Institution 's Global Volcanism Program database of volcanic eruptions in the Holocene Epoch (the last 11,700 years) lists 9,901 confirmed eruptions from 859 volcanoes. The database also lists 1,113 uncertain eruptions and 168 discredited eruptions for

1368-537: Is one of the several tuyas in the area of the Tuya River and Tuya Range in northern British Columbia. Tuya Butte was the first such landform analysed and so its name has entered the geological literature for this kind of volcanic formation. The Tuya Mountains Provincial Park was recently established to protect this unusual landscape, which lies north of Tuya Lake and south of the Jennings River near

1440-471: Is typically low in silica, shield volcanoes are more common in oceanic than continental settings. The Hawaiian volcanic chain is a series of shield cones, and they are common in Iceland , as well. Lava domes are built by slow eruptions of highly viscous lava. They are sometimes formed within the crater of a previous volcanic eruption, as in the case of Mount St. Helens , but can also form independently, as in

1512-617: The Cascade Volcanoes or the Japanese Archipelago , or the eastern islands of Indonesia . Hotspots are volcanic areas thought to be formed by mantle plumes , which are hypothesized to be columns of hot material rising from the core-mantle boundary. As with mid-ocean ridges, the rising mantle rock experiences decompression melting which generates large volumes of magma. Because tectonic plates move across mantle plumes, each volcano becomes inactive as it drifts off

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1584-728: The Igneri people, members of the Arawak group. Around 1300 AD, the Kalinago , or Carib people arrived on the islands. These agriculturalists quickly dispersed the Igneri, and forced them northwards to the Greater Antilles . They named Saint Kitts "Liamuiga" meaning "fertile island", and would likely have expanded further north if not for the arrival of Europeans. A Spanish expedition under Christopher Columbus arrived and claimed

1656-601: The UNESCO World Heritage Site at Brimstone Hill and the now-crumbling Fort Charles . Since 1783, Saint Kitts has been affiliated with the Kingdom of Great Britain , which became the United Kingdom . The island originally produced tobacco , but farmers switched to sugarcane in 1640 because of stiff competition from the colony of Virginia . The labour-intensive cultivation of sugar cane

1728-804: The core–mantle boundary , 3,000 kilometres (1,900 mi) deep within Earth. This results in hotspot volcanism , of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates slide past one another. Large eruptions can affect atmospheric temperature as ash and droplets of sulfuric acid obscure the Sun and cool Earth's troposphere . Historically, large volcanic eruptions have been followed by volcanic winters which have caused catastrophic famines. Other planets besides Earth have volcanoes. For example, volcanoes are very numerous on Venus. Mars has significant volcanoes. In 2009,

1800-834: The landform and may give rise to smaller cones such as Puʻu ʻŌʻō on a flank of Kīlauea in Hawaii. Volcanic craters are not always at the top of a mountain or hill and may be filled with lakes such as with Lake Taupō in New Zealand. Some volcanoes can be low-relief landform features, with the potential to be hard to recognize as such and be obscured by geological processes. Other types of volcano include cryovolcanoes (or ice volcanoes), particularly on some moons of Jupiter , Saturn , and Neptune ; and mud volcanoes , which are structures often not associated with known magmatic activity. Active mud volcanoes tend to involve temperatures much lower than those of igneous volcanoes except when

1872-480: The Middle Range to the southeast. This Middle Range is another stratovolcano 976 m in height with a small summit crater containing a lake. Next in line is the 900 metres (3,000 ft) South East Range, 1 Myr in age, consisting of four peaks. Ottley's dome and Monkey Hill dome are on the flanks, while the older volcanoes represented by Canada Hills, and Conaree Hills lie past the airport and Basseterre on

1944-622: The Philippines, and Mount Vesuvius and Stromboli in Italy. Ash produced by the explosive eruption of stratovolcanoes has historically posed the greatest volcanic hazard to civilizations. The lavas of stratovolcanoes are higher in silica, and therefore much more viscous, than lavas from shield volcanoes. High-silica lavas also tend to contain more dissolved gas. The combination is deadly, promoting explosive eruptions that produce great quantities of ash, as well as pyroclastic surges like

2016-613: The USGS defines a volcano as active whenever subterranean indicators, such as earthquake swarms , ground inflation, or unusually high levels of carbon dioxide or sulfur dioxide are present. The USGS defines a dormant volcano as any volcano that is not showing any signs of unrest such as earthquake swarms, ground swelling, or excessive noxious gas emissions, but which shows signs that it could yet become active again. Many dormant volcanoes have not erupted for thousands of years, but have still shown signs that they may be likely to erupt again in

2088-510: The boundary with the Yukon Territory . Mud volcanoes (mud domes) are formations created by geo-excreted liquids and gases, although several processes may cause such activity. The largest structures are 10 kilometres in diameter and reach 700 meters high. The material that is expelled in a volcanic eruption can be classified into three types: The concentrations of different volcanic gases can vary considerably from one volcano to

2160-402: The case of Lassen Peak . Like stratovolcanoes, they can produce violent, explosive eruptions, but the lava generally does not flow far from the originating vent. Cryptodomes are formed when viscous lava is forced upward causing the surface to bulge. The 1980 eruption of Mount St. Helens was an example; lava beneath the surface of the mountain created an upward bulge, which later collapsed down

2232-481: The dismay of the Nevisians and Anguillans. Anguilla left this arrangement in 1971, after an armed raid on Saint Kitts in 1967. Sugar production continued to dominate the local economy until 2005, when, after 365 years of having a monoculture , the government closed the sugar industry . This decision was made because of huge losses and European Union plans to greatly cut sugar prices. For purposes of governing,

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2304-799: The enormous area they cover, and subsequent concealment under vegetation and glacial deposits, supervolcanoes can be difficult to identify in the geologic record without careful geologic mapping . Known examples include Yellowstone Caldera in Yellowstone National Park and Valles Caldera in New Mexico (both western United States); Lake Taupō in New Zealand; Lake Toba in Sumatra , Indonesia; and Ngorongoro Crater in Tanzania. Volcanoes that, though large, are not large enough to be called supervolcanoes, may also form calderas in

2376-431: The flow is covered with angular, vesicle-poor blocks. Rhyolitic flows typically consist largely of obsidian . Tephra is made when magma inside the volcano is blown apart by the rapid expansion of hot volcanic gases. Magma commonly explodes as the gas dissolved in it comes out of solution as the pressure decreases when it flows to the surface . These violent explosions produce particles of material that can then fly from

2448-610: The formation of a submarine volcano off the coast of Mayotte . Subglacial volcanoes develop underneath ice caps . They are made up of lava plateaus capping extensive pillow lavas and palagonite . These volcanoes are also called table mountains, tuyas , or (in Iceland) mobergs. Very good examples of this type of volcano can be seen in Iceland and in British Columbia . The origin of the term comes from Tuya Butte , which

2520-585: The future. In an article justifying the re-classification of Alaska's Mount Edgecumbe volcano from "dormant" to "active", volcanologists at the Alaska Volcano Observatory pointed out that the term "dormant" in reference to volcanoes has been deprecated over the past few decades and that "[t]he term "dormant volcano" is so little used and undefined in modern volcanology that the Encyclopedia of Volcanoes (2000) does not contain it in

2592-466: The glossaries or index", however the USGS still widely employs the term. Previously a volcano was often considered to be extinct if there were no written records of its activity. Such a generalization is inconsistent with observation and deeper study, as has occurred recently with the unexpected eruption of the Chaitén volcano in 2008. Modern volcanic activity monitoring techniques, and improvements in

2664-475: The industry in 2005. Tourism is a major and growing source of income to the island, although the number and density of resorts is less than on many other Caribbean islands. Transportation , non-sugar agriculture, manufacturing and construction are the other growing sectors of the economy. Saint Kitts is dependent on tourism to drive its economy. Tourism has been increasing since 1978. In 2009, there were 587,479 arrivals to Saint Kitts compared to 379,473 in 2007,

2736-492: The interior of a continent and lead to rifting. Early stages of rifting are characterized by flood basalts and may progress to the point where a tectonic plate is completely split. A divergent plate boundary then develops between the two halves of the split plate. However, rifting often fails to completely split the continental lithosphere (such as in an aulacogen ), and failed rifts are characterized by volcanoes that erupt unusual alkali lava or carbonatites . Examples include

2808-487: The island and offers passenger service from its headquarters near the airport, although the service is geared more for tourists than as day-to-day transportation for residents. Built between 1912 and 1926 to transport sugar cane from farms to the sugar factory in Basseterre, since 2003 the railway has offered a 3.5-hour, 30-mile circle tour of the island on specially designed double-decker open-air coaches, with 12 miles of

2880-564: The island for Spain in 1493. The first English colony was established in 1623, followed by a French colony in 1625. The English and French briefly united to pre-empt a Kalinago ambush. They massacred the local Kalinago , and then partitioned the island, with the English colonists in the middle and the French on either end. In 1629 , a Spanish force sent to clear the islands of foreign settlement seized St. Kitts. The English settlement

2952-613: The island is divided into nine parishes : Saint Kitts & Nevis uses the Eastern Caribbean dollar , which maintains a fixed exchange rate of 2.7-to-one with the United States dollar . The US dollar is almost as widely accepted on the island as the Eastern Caribbean dollar. For hundreds of years, Saint Kitts operated as a sugar monoculture , but due to decreasing profitability, the government closed

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3024-419: The mid-oceanic ridge is above sea level, volcanic islands are formed, such as Iceland . Subduction zones are places where two plates, usually an oceanic plate and a continental plate, collide. The oceanic plate subducts (dives beneath the continental plate), forming a deep ocean trench just offshore. In a process called flux melting , water released from the subducting plate lowers the melting temperature of

3096-551: The modelling of the factors that produce eruptions, have helped the understanding of why volcanoes may remain dormant for a long time, and then become unexpectedly active again. The potential for eruptions, and their style, depend mainly upon the state of the magma storage system under the volcano, the eruption trigger mechanism and its timescale. For example, the Yellowstone volcano has a repose/recharge period of around 700,000 years, and Toba of around 380,000 years. Vesuvius

3168-415: The most dangerous type, are very rare; four are known from the last million years , and about 60 historical VEI 8 eruptions have been identified in the geologic record over millions of years. A supervolcano can produce devastation on a continental scale, and severely cool global temperatures for many years after the eruption due to the huge volumes of sulfur and ash released into the atmosphere. Because of

3240-438: The mud volcano is actually a vent of an igneous volcano. Volcanic fissure vents are flat, linear fractures through which lava emerges. Shield volcanoes, so named for their broad, shield-like profiles, are formed by the eruption of low-viscosity lava that can flow a great distance from a vent. They generally do not explode catastrophically but are characterized by relatively gentle effusive eruptions . Since low-viscosity magma

3312-452: The next. Water vapour is typically the most abundant volcanic gas, followed by carbon dioxide and sulfur dioxide . Other principal volcanic gases include hydrogen sulfide , hydrogen chloride , and hydrogen fluoride . A large number of minor and trace gases are also found in volcanic emissions, for example hydrogen , carbon monoxide , halocarbons , organic compounds, and volatile metal chlorides. The form and style of an eruption of

3384-876: The north side of the mountain. Cinder cones result from eruptions of mostly small pieces of scoria and pyroclastics (both resemble cinders, hence the name of this volcano type) that build up around the vent. These can be relatively short-lived eruptions that produce a cone-shaped hill perhaps 30 to 400 metres (100 to 1,300 ft) high. Most cinder cones erupt only once and some may be found in monogenetic volcanic fields that may include other features that form when magma comes into contact with water such as maar explosion craters and tuff rings . Cinder cones may form as flank vents on larger volcanoes, or occur on their own. Parícutin in Mexico and Sunset Crater in Arizona are examples of cinder cones. In New Mexico , Caja del Rio

3456-447: The northern flank, along with mudflows . This volcano has a crater 900 metres (3,000 ft) wide and 244 metres (801 ft) deep, plus two distinct parasitic domes consisting primarily of andesite , Brimstone Hill and Sandy Point Hill which is coalesced with Farm Flat. Brimstone Hill is noted for having limestone on its flanks, which was dragged upward with the formation of the dome 44,400 years ago. Mt. Liamuiga partially overlays

3528-549: The ocean surface as new islands or floating pumice rafts . In May and June 2018, a multitude of seismic signals were detected by earthquake monitoring agencies all over the world. They took the form of unusual humming sounds, and some of the signals detected in November of that year had a duration of up to 20 minutes. An oceanographic research campaign in May 2019 showed that the previously mysterious humming noises were caused by

3600-420: The ocean surface, due to the rapid cooling effect and increased buoyancy in water (as compared to air), which often causes volcanic vents to form steep pillars on the ocean floor. Hydrothermal vents are common near these volcanoes, and some support peculiar ecosystems based on chemotrophs feeding on dissolved minerals. Over time, the formations created by submarine volcanoes may become so large that they break

3672-471: The ocean's surface. In the deep ocean basins, the tremendous weight of the water prevents the explosive release of steam and gases; however, submarine eruptions can be detected by hydrophones and by the discoloration of water because of volcanic gases . Pillow lava is a common eruptive product of submarine volcanoes and is characterized by thick sequences of discontinuous pillow-shaped masses which form underwater. Even large submarine eruptions may not disturb

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3744-468: The one that destroyed the city of Saint-Pierre in Martinique in 1902. They are also steeper than shield volcanoes, with slopes of 30–35° compared to slopes of generally 5–10°, and their loose tephra are material for dangerous lahars . Large pieces of tephra are called volcanic bombs . Big bombs can measure more than 1.2 metres (4 ft) across and weigh several tons. A supervolcano is defined as

3816-425: The overlying mantle wedge, thus creating magma . This magma tends to be extremely viscous because of its high silica content, so it often does not reach the surface but cools and solidifies at depth . When it does reach the surface, however, a volcano is formed. Thus subduction zones are bordered by chains of volcanoes called volcanic arcs . Typical examples are the volcanoes in the Pacific Ring of Fire , such as

3888-609: The perimeter of the island with smaller roads branching off it; the interior of the island is too steep for habitation. Saint Kitts is 10 km (6.2 mi) away from Sint Eustatius to the north and 3 km (1.9 mi) from Nevis to the south. St. Kitts has three distinct groups of volcanic peaks: the North West or Mount Misery Range; the Middle or Verchilds Range and the South East or Olivees Range. The highest peak

3960-619: The plume, and new volcanoes are created where the plate advances over the plume. The Hawaiian Islands are thought to have been formed in such a manner, as has the Snake River Plain , with the Yellowstone Caldera being part of the North American plate currently above the Yellowstone hotspot . However, the mantle plume hypothesis has been questioned. Sustained upwelling of hot mantle rock can develop under

4032-435: The same time interval. Volcanoes vary greatly in their level of activity, with individual volcanic systems having an eruption recurrence ranging from several times a year to once in tens of thousands of years. Volcanoes are informally described as erupting , active , dormant , or extinct , but the definitions of these terms are not entirely uniform among volcanologists. The level of activity of most volcanoes falls upon

4104-492: The same way; they are often described as "caldera volcanoes". Submarine volcanoes are common features of the ocean floor. Volcanic activity during the Holocene Epoch has been documented at only 119 submarine volcanoes, but there may be more than one million geologically young submarine volcanoes on the ocean floor. In shallow water, active volcanoes disclose their presence by blasting steam and rocky debris high above

4176-622: The solidified erupted material that makes up the mantle of a volcano may be stripped away that its inner anatomy becomes apparent. Using the metaphor of biological anatomy , such a process is called "dissection". Cinder Hill , a feature of Mount Bird on Ross Island , Antarctica , is a prominent example of a dissected volcano. Volcanoes that were, on a geological timescale, recently active, such as for example Mount Kaimon in southern Kyūshū , Japan , tend to be undissected. Eruption styles are broadly divided into magmatic, phreatomagmatic, and phreatic eruptions. The intensity of explosive volcanism

4248-457: The southeast flank. The Salt Dome Peninsula contains the oldest volcanic deposits, 2.3–2.77 Myr in age, consisting of at least nine Pelean domes rising up to 319 metres (1,047 ft) in height, which includes Williams Hill and St. Anthony's Peak . During the last ice age , the sea level was up to 91 metres (300 ft) lower and St. Kitts and Nevis were one island along with Saba and Sint Eustatius (also known as Statia). St. Kitts

4320-406: The surrounding areas, and initially not seismically monitored before its unanticipated and catastrophic eruption of 1991. Two other examples of volcanoes that were once thought to be extinct, before springing back into eruptive activity were the long-dormant Soufrière Hills volcano on the island of Montserrat , thought to be extinct until activity resumed in 1995 (turning its capital Plymouth into

4392-434: The theory of plate tectonics. For example, some volcanoes are polygenetic with more than one period of activity during their history; other volcanoes that become extinct after erupting exactly once are monogenetic (meaning "one life") and such volcanoes are often grouped together in a geographical region. At the mid-ocean ridges , two tectonic plates diverge from one another as hot mantle rock creeps upwards beneath

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4464-444: The thinned oceanic crust . The decrease of pressure in the rising mantle rock leads to adiabatic expansion and the partial melting of the rock, causing volcanism and creating new oceanic crust. Most divergent plate boundaries are at the bottom of the oceans, and so most volcanic activity on Earth is submarine, forming new seafloor . Black smokers (also known as deep sea vents) are evidence of this kind of volcanic activity. Where

4536-546: The trip being by bus. Saint Kitts is or was the residence of: Volcanic A volcano is a rupture in the crust of a planetary-mass object , such as Earth , that allows hot lava , volcanic ash , and gases to escape from a magma chamber below the surface. The process that forms volcanoes is called volcanism . On Earth, volcanoes are most often found where tectonic plates are diverging or converging , and because most of Earth's plate boundaries are underwater, most volcanoes are found underwater. For example,

4608-431: The underlying ductile mantle , and most volcanic activity on Earth takes place along plate boundaries, where plates are converging (and lithosphere is being destroyed) or are diverging (and new lithosphere is being created). During the development of geological theory, certain concepts that allowed the grouping of volcanoes in time, place, structure and composition have developed that ultimately have had to be explained in

4680-492: The volcano. Solid particles smaller than 2 mm in diameter ( sand-sized or smaller) are called volcanic ash. Tephra and other volcaniclastics (shattered volcanic material) make up more of the volume of many volcanoes than do lava flows. Volcaniclastics may have contributed as much as a third of all sedimentation in the geologic record. The production of large volumes of tephra is characteristic of explosive volcanism. Through natural processes, mainly erosion , so much of

4752-424: The volcanoes of the East African Rift . A volcano needs a reservoir of molten magma (e.g. a magma chamber), a conduit to allow magma to rise through the crust, and a vent to allow the magma to escape above the surface as lava. The erupted volcanic material (lava and tephra) that is deposited around the vent is known as a volcanic edifice , typically a volcanic cone or mountain. The most common perception of

4824-432: Was abolished by an Act of Parliament which became law on 1 August 1834. This emancipation was followed by four years of forced enslavement, put in place to protect the "planters" (plantation owners) from losing their free labour force. 1 August is now celebrated as a public holiday and is called Emancipation Day . In 1883, Saint Kitts, Nevis , and Anguilla were all linked under one presidency, located on Saint Kitts, to

4896-421: Was described by Roman writers as having been covered with gardens and vineyards before its unexpected eruption of 79 CE , which destroyed the towns of Herculaneum and Pompeii . Accordingly, it can sometimes be difficult to distinguish between an extinct volcano and a dormant (inactive) one. Long volcano dormancy is known to decrease awareness. Pinatubo was an inconspicuous volcano, unknown to most people in

4968-493: Was formerly a common diminutive of "Christopher". Brimstone Hill Fortress National Park , a UNESCO World Heritage Site , is the largest fortress ever built in the Eastern Caribbean. The island of Saint Kitts is home to the Warner Park Cricket Stadium , which was used to host 2007 Cricket World Cup matches. This made Saint Kitts and Nevis the smallest nation to ever host a World Cup event . Saint Kitts

5040-521: Was originally settled by pre-agricultural, pre-ceramic "Archaic people", who migrated south down the archipelago from Florida. In a few hundred years they disappeared, to be replaced by the ceramic -using and agriculturalist Saladoid people around 100 BC, who migrated to St. Kitts north up the archipelago from the banks of the Orinoco River in Venezuela . Around 800 AD, they were replaced by

5112-541: Was rebuilt following the 1630 peace between England and Spain. The island alternated repeatedly between English (then British ) and French control during the 17th and 18th centuries, as one power took the whole island, only to have it switch hands due to treaties or military action. Actions included the Siege of Brimstone Hill and the Battle of Saint Kitts . Parts of the island were heavily fortified, as exemplified by

5184-497: Was the reason for the large-scale importation of African slaves . The importation began almost immediately upon the arrival of Europeans to the region even though sugarcane wasn't cultivated for another two hundred years on the island, leading some to discredit the earliest claims of imported African labour. The purchasing of enslaved Africans was outlawed in the British Empire by an Act of Parliament in 1807. Slavery

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