Novarupta is a volcano, formed in 1912, located on the Alaska Peninsula in Katmai National Park and Preserve, about 290 miles southwest of Anchorage. Formed during the largest volcanic eruption of the 20th century, Novarupta released 30 times the volume of magma of the 1980 eruption of Mount St. Helens; the 1912 eruption that formed Novarupta was the largest to occur during the 20th century. It began on June 6, 1912, culminated in a series of violent eruptions. Rated a 6 on the Volcanic Explosivity Index, the 60-hour-long eruption expelled 3.1 to 3.6 cubic miles of ash, thirty times as much as the 1980 eruption of Mount St. Helens; the erupted magma of rhyolite and andesite resulted in more than 4.1 cubic miles of air fall tuff and 2.6 cubic miles of pyroclastic ash-flow tuff. During the 20th century, only the 1991 eruption of Mount Pinatubo in the Philippines and the 1902 eruption of Santa María in Guatemala were of comparable magnitude. At least two larger eruptions occurred in the Dutch East Indies during the 19th century: the 1815 eruption of Tambora and the 1883 eruption of Krakatoa.
The Novarupta eruption occurred about 2.5 mi from the peak of Mount Katmai Volcano and 4,000 ft below the post-eruption Mount Katmai summit. During the eruption a large quantity of magma erupted from beneath the Mount Katmai area, resulting in the formation of a 1.2-mile wide, funnel-shaped vent and the collapse of Mount Katmai's summit, creating a 2,000-foot deep, 1.9 by 2.5 mi caldera. The eruption ended with the extrusion of a lava dome of rhyolite; the 295-foot high and 1,180-foot wide dome it created forms what is now referred to as Novarupta. Despite the magnitude of the eruption, no deaths directly resulted. Eye witness accounts from people located downwind in the path of a thick ash cloud describe the gradual lowering of visibility to next to nothing. Ash threatened to contaminate drinking water and decimate food resources, but the native Alaskans were aided in their survival by traditional knowledge passed down through generations from previous eruptions; however the native villages experiencing the heaviest ash falls were abandoned and the inhabitants relocated.
The eruption is said to have had an effect on the level of the Nile. Pyroclastic ash flow from the eruption formed the Valley of Ten Thousand Smokes, named by botanist Robert F. Griggs, who explored the volcano's aftermath for the National Geographic Society in 1916; the eruption forming the Valley of Ten Thousand Smokes is one of the few in recorded history to have produced welded tuff, producing numerous fumaroles that persisted for 15 years. Established as a National Park & Preserve in 1980, Katmai is located on the Alaska Peninsula, across from Kodiak Island, with headquarters in nearby King Salmon, about 290 mi southwest of Anchorage; the area was designated a National Monument in 1918 to protect the area around the 1912 eruption of Novarupta and the 40-square-mile, 100-to-700-foot deep, pyroclastic flow of the Valley of Ten Thousand Smokes. List of volcanoes in the United States Timeline of volcanism on Earth Parícutin, a cinder cone volcano in Mexico whose emergence could be observed.
USGS collection of descriptions of Novarupta USGS QuickTime video clip on Novarupta geology.com, Novarupta – topographic maps, annotated satellite images Alaska Volcano Observatory: Novarupta USGS Photographic Library – novarupta
Spirit known as MER-A or MER-2, is a robotic rover on Mars, active from 2004 to 2010. It was one of two rovers of NASA's Mars Exploration Rover Mission, it landed on Mars at 04:35 Ground UTC on January 4, 2004, three weeks before its twin, which landed on the other side of the planet. Its name was chosen through a NASA-sponsored student essay competition; the rover became stuck in a "sand trap" in late 2009 at an angle that hampered recharging of its batteries. The rover completed its planned 90-sol mission. Aided by cleaning events that resulted in more energy from its solar panels, Spirit went on to function over twenty times longer than NASA planners expected. Spirit logged 7.73 km of driving instead of the planned 600 m, allowing more extensive geological analysis of Martian rocks and planetary surface features. Initial scientific results from the first phase of the mission were published in a special issue of the journal Science. On May 1, 2009, Spirit became stuck in soft soil; this was not the first of the mission's "embedding events" and for the following eight months NASA analyzed the situation, running Earth-based theoretical and practical simulations, programming the rover to make extrication drives in an attempt to free itself.
These efforts continued until January 26, 2010 when NASA officials announced that the rover was irrecoverably obstructed by its location in soft soil, though it continued to perform scientific research from its current location. The rover continued in a stationary science platform role until communication with Spirit stopped on March 22, 2010. JPL continued to attempt to regain contact until May 24, 2011, when NASA announced that efforts to communicate with the unresponsive rover had ended, calling the mission complete. A formal farewell took place at NASA headquarters shortly thereafter; the Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Office of Space Science, Washington. The primary surface mission for Spirit was planned to last at least 90 sols; the mission lasted about 2,208 sols. On August 11, 2007, Spirit obtained the second longest operational duration on the surface of Mars for a lander or rover at 1282 Sols, one sol longer than the Viking 2 lander.
Viking 2 was powered by a nuclear cell. Until Opportunity overtook it on May 19, 2010, the Mars probe with longest operational period was Viking 1 that lasted for 2245 Sols on the surface of Mars. On March 22, 2010, Spirit sent its last communication, thus falling just over a month short of surpassing Viking 1's operational record. An archive of weekly updates on the rover's status can be found at the Spirit Update Archive. Spirit's total odometry as of March 22, 2010 is 7,730.50 meters. The scientific objectives of the Mars Exploration Rover mission were to: Search for and characterize a variety of rocks and soils that hold clues to past water activity. In particular, samples sought will include those that have minerals deposited by water-related processes such as precipitation, sedimentary cementation or hydrothermal activity. Determine the distribution and composition of minerals and soils surrounding the landing sites. Determine what geologic processes have shaped the local terrain and influenced the chemistry.
Such processes could include water or wind erosion, hydrothermal mechanisms and cratering. Perform calibration and validation of surface observations made by Mars Reconnaissance Orbiter instruments; this will help determine the accuracy and effectiveness of various instruments that survey Martian geology from orbit. Search for iron-containing minerals and quantify relative amounts of specific mineral types that contain water or were formed in water, such as iron-bearing carbonates. Characterize the mineralogy and textures of rocks and soils and determine the processes that created them. Search for geological clues to the environmental conditions that existed when liquid water was present. Assess whether those environments were conducive to life. NASA sought evidence of life on Mars, beginning with the question of whether the Martian environment was suitable for life. Life forms known to science require water, so the history of water on Mars is a critical piece of knowledge. Although the Mars Exploration Rovers did not have the ability to detect life directly, they offered important information on the habitability of the environment during the planet's history.
Spirit are six-wheeled, solar-powered robots standing 1.5 meters high, 2.3 meters wide and 1.6 meters long and weighing 180 kilograms. Six wheels on a rocker-bogie system enable mobility over rough terrain; each wheel has its own motor. The vehicle is steered at front and rear and is designed to operate safely at tilts of up to 30 degrees. Maximum speed is 5 centimeters per second. Both Spirit and Opportunity have pieces of the fallen World Trade Center's metal on them that were "turned into shields to protect cables on the drilling mechanisms". Solar arrays generate about 140 watts for up to four hours per Martian day while rechargeable lithium ion batteries store energy for use at night. Spirit's onboard computer uses a 20 MHz RAD6000 CPU with 128 MB of DRAM, 3 MB o
Sicily is the largest island in the Mediterranean Sea and one of the 20 regions of Italy. It is one of the five Italian autonomous regions, in Southern Italy along with surrounding minor islands referred to as Regione Siciliana. Sicily is located in the central Mediterranean Sea, south of the Italian Peninsula, from which it is separated by the narrow Strait of Messina, its most prominent landmark is Mount Etna, the tallest active volcano in Europe, one of the most active in the world 3,329 m high. The island has a typical Mediterranean climate; the earliest archaeological evidence of human activity on the island dates from as early as 12,000 BC. By around 750 BC, Sicily had three Phoenician and a dozen Greek colonies and, for the next 600 years, it was the site of the Sicilian Wars and the Punic Wars. After the fall of the Roman Empire in the 5th century AD, Sicily was ruled during the Early Middle Ages by the Vandals, the Ostrogoths, the Byzantine Empire, the Emirate of Sicily; the Norman conquest of southern Italy led to the creation of the Kingdom of Sicily, subsequently ruled by the Hohenstaufen, the Capetian House of Anjou and the House of Habsburg.
It was unified under the House of Bourbon with the Kingdom of Naples as the Kingdom of the Two Sicilies. It became part of Italy in 1860 following the Expedition of the Thousand, a revolt led by Giuseppe Garibaldi during the Italian unification, a plebiscite. Sicily was given special status as an autonomous region on 15th May 1946, 18 days before the Italian constitutional referendum of 1946. Albeit, much of the autonomy still remains unapplied financial autonomy, because the autonomy-activating laws have been deferred to be approved by the parithetic committee, since 1946. Sicily has a rich and unique culture with regard to the arts, literature and architecture, it is home to important archaeological and ancient sites, such as the Necropolis of Pantalica, the Valley of the Temples and Selinunte. Sicily has a triangular shape, earning it the name Trinacria. To the east, it is separated from the Italian mainland by the Strait of Messina, about 3 km wide in the north, about 16 km wide in the southern part.
The northern and southern coasts are each about 280 km long measured as a straight line, while the eastern coast measures around 180 km. The total area of the island is 25,711 km2, while the Autonomous Region of Sicily has an area of 27,708 km2; the terrain of inland Sicily is hilly and is intensively cultivated wherever possible. Along the northern coast, the mountain ranges of Madonie, 2,000 m, Nebrodi, 1,800 m, Peloritani, 1,300 m, are an extension of the mainland Apennines; the cone of Mount Etna dominates the eastern coast. In the southeast lie the lower Hyblaean Mountains, 1,000 m; the mines of the Enna and Caltanissetta districts were part of a leading sulphur-producing area throughout the 19th century, but have declined since the 1950s. Sicily and its surrounding small islands have some active volcanoes. Mount Etna is the largest active volcano in Europe and still casts black ash over the island with its ever-present eruptions, it stands 3,329 metres high, though this varies with summit eruptions.
It is the highest mountain in Italy south of the Alps. Etna covers an area of 1,190 km2 with a basal circumference of 140 km; this makes it by far the largest of the three active volcanoes in Italy, being about two and a half times the height of the next largest, Mount Vesuvius. In Greek mythology, the deadly monster Typhon was trapped under the mountain by Zeus, the god of the sky. Mount Etna is regarded as a cultural symbol and icon of Sicily; the Aeolian Islands in the Tyrrhenian Sea, to the northeast of mainland Sicily form a volcanic complex, include Stromboli. The three volcanoes of Vulcano and Lipari are currently active, although the latter is dormant. Off the southern coast of Sicily, the underwater volcano of Ferdinandea, part of the larger Empedocles volcano, last erupted in 1831, it is located between the island of Pantelleria. The autonomous region includes several neighbouring islands: the Aegadian Islands, the Aeolian Islands and Lampedusa; the island is drained by several rivers, most of which flow through the central area and enter the sea at the south of the island.
The Salso flows through parts of Enna and Caltanissetta before entering the Mediterranean Sea at the port of Licata. To the east, the Alcantara flows through the province of Messina and enters the sea at Giardini Naxos, the Simeto, which flows into the Ionian Sea south of Catania. Other important rivers on the island are the Platani in the southwest. Sicily has a typical Mediterranean climate with mild and wet winters and hot, dry summers with changeable intermediate seasons. On the coasts the south-western, the climate is affected by the African currents and summers can be scorching. Sicily is seen as an island of warm winters but above all along the Tyrrhenian coast and in the inland areas, winters can be cold, with typical continental climate. Snow falls in abundance above 900–1000 metres, but stronger cold waves can carry it in the hills and in coastal cities on the northern coast of the island; the interi
Igneous rock, or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava; the magma can be crust. The melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form natural glasses. Igneous rocks occur in a wide range of geological settings: shields, orogens, large igneous provinces, extended crust and oceanic crust. Igneous and metamorphic rocks make up 90–95% of the top 16 km of the Earth's crust by volume. Igneous rocks form about 15% of the Earth's current land surface. Most of the Earth's oceanic crust is made of igneous rock. Igneous rocks are geologically important because: their minerals and global chemistry give information about the composition of the mantle, from which some igneous rocks are extracted, the temperature and pressure conditions that allowed this extraction, and/or of other pre-existing rock that melted.
In terms of modes of occurrence, igneous rocks can be either extrusive. Intrusive igneous rocks make up the majority of igneous rocks and are formed from magma that cools and solidifies within the crust of a planet, surrounded by pre-existing rock; the mineral grains in such rocks can be identified with the naked eye. Intrusive rocks can be classified according to the shape and size of the intrusive body and its relation to the other formations into which it intrudes. Typical intrusive formations are batholiths, laccoliths and dikes; when the magma solidifies within the earth's crust, it cools forming coarse textured rocks, such as granite, gabbro, or diorite. The central cores of major mountain ranges consist of intrusive igneous rocks granite; when exposed by erosion, these cores may occupy huge areas of the Earth's surface. Intrusive igneous rocks that form at depth within the crust are termed plutonic rocks and are coarse-grained. Intrusive igneous rocks that form near the surface are termed subvolcanic or hypabyssal rocks and they are medium-grained.
Hypabyssal rocks are less common than plutonic or volcanic rocks and form dikes, laccoliths, lopoliths, or phacoliths. Extrusive igneous rocks known as volcanic rocks, are formed at the crust's surface as a result of the partial melting of rocks within the mantle and crust. Extrusive solidify quicker than intrusive igneous rocks, they are formed by the cooling of molten magma on the earth's surface. The magma, brought to the surface through fissures or volcanic eruptions, solidifies at a faster rate. Hence such rocks are smooth and fine-grained. Basalt is lava plateaus; some kinds of basalt solidify to form long polygonal columns. The Giant's Causeway in Antrim, Northern Ireland is an example; the molten rock, with or without suspended crystals and gas bubbles, is called magma. It rises; when magma reaches the surface from beneath water or air, it is called lava. Eruptions of volcanoes into air are termed subaerial, whereas those occurring underneath the ocean are termed submarine. Black smokers and mid-ocean ridge basalt are examples of submarine volcanic activity.
The volume of extrusive rock erupted annually by volcanoes varies with plate tectonic setting. Extrusive rock is produced in the following proportions: divergent boundary: 73% convergent boundary: 15% hotspot: 12%. Magma that erupts from a volcano behaves according to its viscosity, determined by temperature, crystal content and the amount of silica. High-temperature magma, most of, basaltic in composition, behaves in a manner similar to thick oil and, as it cools, treacle. Long, thin basalt flows with pahoehoe surfaces are common. Intermediate composition magma, such as andesite, tends to form cinder cones of intermingled ash and lava, may have a viscosity similar to thick, cold molasses or rubber when erupted. Felsic magma, such as rhyolite, is erupted at low temperature and is up to 10,000 times as viscous as basalt. Volcanoes with rhyolitic magma erupt explosively, rhyolitic lava flows are of limited extent and have steep margins, because the magma is so viscous. Felsic and intermediate magmas that erupt do so violently, with explosions driven by the release of dissolved gases—typically water vapour, but carbon dioxide.
Explosively erupted pyroclastic material is called tephra and includes tuff and ignimbrite. Fine volcanic ash is erupted and forms ash tuff deposits, which ca
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries a name of the Roman god of war, is referred to as the "Red Planet" because the reddish iron oxide prevalent on its surface gives it a reddish appearance, distinctive among the astronomical bodies visible to the naked eye. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the valleys and polar ice caps of Earth; the days and seasons are comparable to those of Earth, because the rotational period as well as the tilt of the rotational axis relative to the ecliptic plane are similar. Mars is the site of Olympus Mons, the largest volcano and second-highest known mountain in the Solar System, of Valles Marineris, one of the largest canyons in the Solar System; the smooth Borealis basin in the northern hemisphere covers 40% of the planet and may be a giant impact feature. Mars has two moons and Deimos, which are small and irregularly shaped.
These may be captured asteroids, similar to a Mars trojan. There are ongoing investigations assessing the past habitability potential of Mars, as well as the possibility of extant life. Future astrobiology missions are planned, including the Mars 2020 and ExoMars rovers. Liquid water cannot exist on the surface of Mars due to low atmospheric pressure, less than 1% of the Earth's, except at the lowest elevations for short periods; the two polar ice caps appear to be made of water. The volume of water ice in the south polar ice cap, if melted, would be sufficient to cover the entire planetary surface to a depth of 11 meters. In November 2016, NASA reported finding a large amount of underground ice in the Utopia Planitia region of Mars; the volume of water detected has been estimated to be equivalent to the volume of water in Lake Superior. Mars can be seen from Earth with the naked eye, as can its reddish coloring, its apparent magnitude reaches −2.94, surpassed only by Jupiter, the Moon, the Sun.
Optical ground-based telescopes are limited to resolving features about 300 kilometers across when Earth and Mars are closest because of Earth's atmosphere. Mars is half the diameter of Earth with a surface area only less than the total area of Earth's dry land. Mars is less dense than Earth, having about 15% of Earth's volume and 11% of Earth's mass, resulting in about 38% of Earth's surface gravity; the red-orange appearance of the Martian surface is caused by rust. It can look like butterscotch. Like Earth, Mars has differentiated into a dense metallic core overlaid by less dense materials. Current models of its interior imply a core with a radius of about 1,794 ± 65 kilometers, consisting of iron and nickel with about 16–17% sulfur; this iron sulfide core is thought to be twice as rich in lighter elements as Earth's. The core is surrounded by a silicate mantle that formed many of the tectonic and volcanic features on the planet, but it appears to be dormant. Besides silicon and oxygen, the most abundant elements in the Martian crust are iron, aluminum and potassium.
The average thickness of the planet's crust is about 50 km, with a maximum thickness of 125 km. Earth's crust averages 40 km. Mars is a terrestrial planet that consists of minerals containing silicon and oxygen and other elements that make up rock; the surface of Mars is composed of tholeiitic basalt, although parts are more silica-rich than typical basalt and may be similar to andesitic rocks on Earth or silica glass. Regions of low albedo suggest concentrations of plagioclase feldspar, with northern low albedo regions displaying higher than normal concentrations of sheet silicates and high-silicon glass. Parts of the southern highlands include detectable amounts of high-calcium pyroxenes. Localized concentrations of hematite and olivine have been found. Much of the surface is covered by finely grained iron oxide dust. Although Mars has no evidence of a structured global magnetic field, observations show that parts of the planet's crust have been magnetized, suggesting that alternating polarity reversals of its dipole field have occurred in the past.
This paleomagnetism of magnetically susceptible minerals is similar to the alternating bands found on Earth's ocean floors. One theory, published in 1999 and re-examined in October 2005, is that these bands suggest plate tectonic activity on Mars four billion years ago, before the planetary dynamo ceased to function and the planet's magnetic field faded, it is thought that, during the Solar System's formation, Mars was created as the result of a stochastic process of run-away accretion of material from the protoplanetary disk that orbited the Sun. Mars has many distinctive chemical features caused by its position in the Solar System. Elements with comparatively low boiling points, such as chlorine and sulphur, are much more common on Mars than Earth. After the formation of the planets, all were subjected to the so-called "Late Heavy Bombardment". About 60% of the surface of Mars shows a record of impacts from that era, whereas much of the remaining surface is underlain by immense impact basins caused by those events.
There is evidence of an enormous impact basin in the northern hemisphere of Mars, spanning 10,600 by 8,500 km, or four times the size of the Moon's South Pole – Aitk
Whakaari / White Island
Whakaari / White Island is an active andesite stratovolcano, situated 48 km from the east coast of the North Island of New Zealand, in the Bay of Plenty. It is New Zealand's most active cone volcano, has been built up by continuous volcanic activity over the past 150,000 years; the nearest mainland towns are Tauranga. White Island has been in a nearly continuous stage of releasing volcanic gas at least since it was discovered by James Cook in 1769; the island is circular, about 2 km in diameter, rises to a height of 321 m above sea level. It covers an area of 325 ha; the exposed island is only the peak of a much larger submarine mountain, which rises up to 1,600 m above the nearby seafloor. Sulphur mining was attempted but was abandoned in 1914 after a lahar killed all of the site's workers; the main activities on the island now are guided scientific research. Whakaari is part of the Taupo Volcanic Zone, its eruptions have produced explosive eruptions of ash. Its frequent activity and easy access attract scientists and volcanologists as well as many tourists.
Volcanologists from the GeoNet Project continually monitor the volcano's activity via surveillance cameras. Survey pegs and seismograph equipment for early earthquake warnings via radio have been installed on the crater walls; the island is on an alert level rating of 1 or 2 on a scale of 0 to 5. This volcano is monitored by the Deep Earth Carbon Degassing Project. At most times the volcanic activity is limited to boiling mud. In March 2000, three small vents appeared in the main crater and began belching ash which covered the island in fine grey powder. An eruption on 27 July 2000 blanketed the island with mud and scoria and a new crater appeared. Major eruptions in 1981–83 altered much of the island's landscape and destroyed the extensive pōhutukawa forest; the large crater created at that time now contains a lake. Between July and August 2012 White Island showed signs of increased activity with lake and gas levels rising from inside the crater. On 5 August 2012 a minor eruption occurred. More eruptions have followed since.
Continued volcanic activity and tremors on 25 January 2013 suggested. A small eruption occurred on 20 August 2013 at 10.23am, lasting for 10 minutes and producing steam. According to The New Zealand Herald newspaper, "Civil Defence will monitor White Island following a small eruption which could be part of a sequence leading to a bigger event." The full Māori name for the island is'Te Puia o Whakaari', meaning'The Dramatic Volcano.' It was named'White Island' by Captain Cook on 1 October 1769 due to the white steam emanating from it. Although Cook went close to the island he did not record. Attempts were made in the mid-1880s, 1898–1901 and 1913–1914 to mine sulphur from White Island, with the island at first being owned by John Wilson; the mining came to a halt in September 1914, when part of the western crater rim collapsed, creating a lahar which killed all 10 workers. They disappeared without trace, only a camp cat survived, it was found some days afterwards by the resupply ship, dubbed "Peter the Great".
Some years in 1923, mining was again attempted, but learning from the 1914 disaster, the miners built their huts on a flat part of the island near a gannet colony. Each day they would lower their boat into the sea from a gantry, row around to the mining factory wharf in Crater Bay. If the sea was rough they had to clamber around the rocks on a narrow track on the crater's edge. Before the days of antibiotics, sulphur was used in medicines as an antibacterial agent, in the making of match-heads, for sterilising wine corks; the miner's diggings were handled in small rail trucks to the crushing and bagging process in the factory built on the island. There was not enough sulphur at Whakaari and so the ground-up rock was used as a component of agricultural fertiliser; the mining ended in the 1930s because of the poor mineral content in the fertiliser. The remains of the buildings can still be seen, much corroded by the sulphuric gases; the island has been identified as an Important Bird Area by BirdLife International because of its breeding colony of about 3000 pairs of Australasian gannets.
White Island is owned. It was declared a private scenic reserve, in 1953, is subject to the provision of the Reserves Act 1977. Visitors cannot land without permission. However, it is accessible by authorised tourist operators; the waters surrounding White Island are well known for their fishing. Yellowtail kingfish abound all year round, there is deep water fishing for hapuka and bluenose in the winter and blue and striped marlin and yellowfin tuna in the summer. A small charter fleet offering day trips and overnight or longer trips operates from the nearby port at Whakatane. List of islands of New Zealand List of volcanoes in New Zealand Volcanology of New Zealand "White Island". Global Volcanism Program. Smithsonian Institution. Retrieved 2009-01-01. Volcanic Hazards at White Island Volcano World: White Island White Island crater volcano camera Whakaari Trust
Vulcano or "Vulcan" is a small volcanic island in the Tyrrhenian Sea, about 25 km north of Sicily and located at the southernmost end of the eight Aeolian Islands. The island is 21 km2 in area, rises to 501 m above sea level, it contains several volcanic caldera, including one of the four active volcanoes in Italy that are not submarine; the word "volcano" and its equivalent in several European languages derive from the name of this island, which in turn derives from Vulcan, the Roman god of fire. The Romans used the island for raw materials, harvesting timber, mining alum and sulfur; these were the principal activities on the island until the end of the 19th Century. After the Bourbon rule collapsed in 1860, a Briton named James Stevenson bought the northern part of the island, built a villa, reopened the local mines, planted vineyards for making Malmsey wine. Stevenson lived on Vulcano until the last major eruption on the island happened in 1888; this eruption lasted the better part of two years, by which time Stevenson had sold all of his property to the local populace.
He never returned to the island. His villa is still intact; the volcanic activity in the region is the result of the northward-moving African Plate meeting the Eurasian Plate. There are three volcanic centres on the island: At the southern end of the island are old stratovolcano cones, Monte Aria, Monte Saraceno and Monte Luccia, which have collapsed into the Il Piano Caldera; the most active centre is the Gran Cratere at the top of the Fossa cone, the cone having grown in the Lentia Caldera in the middle of the island, has had at least nine major eruptions in the last 6000 years. At the north of the island is Vulcanello, connected to the rest of it by an isthmus, flooded in bad weather, it emerged from the sea during an eruption in 183 BCE as a separate islet. Occasional eruptions from its three cones with both pyroclastic flow deposits and lavas occurred from until 1550, with the last eruption creating a narrow isthmus connecting it to Vulcano. Vulcano has been quiet since the eruption of the Fossa cone on 3 August 1888 to 1890, which deposited about 5 m of pyroclastic material on the summit.
The style of eruption seen on the Fossa cone is called a Vulcanian eruption, being the explosive emission of pyroclastic fragments of viscous magmas caused by the high viscosity preventing gases from escaping easily. This eruption of Vulcano was documented at the time by Giuseppe Mercalli. Mercalli described the eruptions as "... Explosions sounding like a cannon at irregular intervals..." As a result, vulcanian eruptions are based on this description. A typical vulcanian eruption can hurl blocks of solid material several hundreds of metres from the vent. Mercalli reported blocks from the 1888-1890 eruption fell in the sea between Vulcano and Lipari, several were photographed by him or his assistants that had fallen on the island of Vulcano. Volcanic gas emissions from this volcano are measured by a multicomponent gas analyzer system, which detects degassing of rising magmas before an eruption, improving prediction of volcanic activity. A survey on local groundwater occurred during 1995–1997 showed temperatures up to 49–75°C, sodium sulfate-chloride chemical composition and near neutral pH in the water wells closest to the slopes of the volcanic cone.
This is due to condensation of to the slopes of the volcanic cone and water-rock interaction buffering. Since Vulcano island has volcanic activity, it is a place where thermophiles and hyperthermophiles are to be found. In fact, the hyperthermophilic archaea Pyrococcus furiosus was described for the first time when it was isolated from sediments of this island by Gerhard Fiala and Karl Stetter; the Ancient Greeks named the island Thérmessa. The island appeared in their myths as the private foundry of the Olympian god Hephaestus, the patron of blacksmiths, he had another two foundries at Olympus. Strabo mentions Thermessa as sacred place of Hephaestus, but it is not clear if it was a third name for the island, or just an adjective; the Romans believed that Vulcano was the chimney of the god Vulcan's workshop and therefore named the island after him. The island had grown due to his periodic clearing of ashes from his forge; the earthquakes that either preceded or accompanied the explosions of ash were considered to be due to Vulcan making weapons for the god Mars and his armies to wage war.
The motion picture Vulcano was filmed on Vulcano and the nearby island of Salina between 1949 and 1950. An asteroid is named for 4464 Vulcano; the island of Vulcano is featured in the Battle Tendency story arc of the manga JoJo's Bizarre Adventure by Hirohiko Araki, as the scene of the final clash between the protagonist Joseph Joestar and the antagonist Kars, leader of the Pillar Men. In the opinion of the American attorney and writer Richard Paul Roe, the play The Tempest by William Shakespeare is set on the island of Vulcano. List of volcanoes in Italy List of islands of Italy Vulcan Vulcano a 1950 Italian drama film set on the island. Ezio Giunta, dir.. "Vulcano". Estateolie 2005*The Essential Guide: 80–87. "Vulcano". Global Volcanism Program. Smithsonian Institution. Retrieved 2008-12-18. Photos and explanatory captions