Volcanoes: Wikis

  

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Cleveland Volcano in the Aleutian Islands of Alaska photographed from the International Space Station, May 2006
Volcano scheme.svg
Cross-section through a stratovolcano (vertical scale is exaggerated):
1. Large magma chamber
2. Bedrock
3. Conduit (pipe)
4. Base
5. Sill
6. Dike
7. Layers of ash emitted by the volcano
8. Flank
9. Layers of lava emitted by the volcano
10. Throat
11. Parasitic cone
12. Lava flow
13. Vent
14. Crater
15. Ash cloud
Pinatubo ash plume reaching a height of 19 km, 3 days before the climactic eruption of 15 June 1991
A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot magma, ash and gases to escape from below the surface. The word volcano is derived from the name of Vulcano island off Sicily which in turn, was named after Vulcan, the Roman god of fire.[1]
Volcanoes are generally found where tectonic plates are diverging or converging. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are usually not created where two tectonic plates slide past one another. Volcanoes can also form where there is stretching and thinning of the Earth's crust (called "non-hotspot intraplate volcanism"), such as in the African Rift Valley, the Wells Gray-Clearwater volcanic field and the Rio Grande Rift in North America and the European Rhine Graben with its Eifel volcanoes.
Volcanoes can be caused by mantle plumes. These so-called hotspots, for example at Hawaii, can occur far from plate boundaries. Hotspot volcanoes are also found elsewhere in the solar system, especially on rocky planets and moons.

Contents

Etymology

Kircher's model of the Earth's internal fires, from Mundus Subterraneus
The word volcano is thought to derive from Vulcano, a volcanic island in the Aeolian Islands of Italy whose name in turn originates from Vulcan, the name of a god of fire in Roman mythology. The study of volcanoes is called volcanology, sometimes spelled vulcanology.

Plate tectonics and hotspots

Map showing the divergent plate boundaries (OSR – Oceanic Spreading Ridges) and recent sub aerial volcanoes.

Divergent plate boundaries

At the mid-oceanic ridges, two tectonic plates diverge from one another. New oceanic crust is being formed by hot molten rock slowly cooling and solidifying. The crust is very thin at mid-oceanic ridges due to the pull of the tectonic plates. The release of pressure due to the thinning of the crust leads to adiabatic expansion, and the partial melting of the mantle causing volcanism and creating new oceanic crust. Most divergent plate boundaries are at the bottom of the oceans, therefore most volcanic activity is submarine, forming new seafloor. Black smokers or deep sea vents are an example of this kind of volcanic activity. Where the mid-oceanic ridge is above sea-level, volcanic islands are formed, for example, Iceland.
Indonesia - Lombok: Mount Rinjani - outbreak in 1994

Convergent plate boundaries

Subduction zones are places where two plates, usually an oceanic plate and a continental plate, collide. In this case, the oceanic plate subducts, or submerges under the continental plate forming a deep ocean trench just offshore. Water released from the subducting plate lowers the melting temperature of the overlying mantle wedge, creating magma. This magma tends to be very viscous due to its high silica content, so often does not reach the surface and cools at depth. When it does reach the surface, a volcano is formed. Typical examples for this kind of volcano are Mount Etna and the volcanoes in the Pacific Ring of Fire.

Hotspots

Hotspots are not usually located on the ridges of tectonic plates, but above mantle plumes, where the convection of the Earth's mantle creates a column of hot material that rises until it reaches the crust, which tends to be thinner than in other areas of the Earth. The temperature of the plume causes the crust to melt and form pipes, which can vent magma. Because the tectonic plates move whereas the mantle plume remains in the same place, each volcano becomes dormant after a while and a new volcano is then formed as the plate shifts over the hotspot. The Hawaiian Islands are thought to be formed in such a manner, as well as the Snake River Plain, with the Yellowstone Caldera being the part of the North American plate currently above the hot spot.

Volcanic features

Conical Mount Fuji in Japan, at sunrise from Lake Kawaguchi (2005)
The most common perception of a volcano is of a conical mountain, spewing lava and poisonous gases from a crater at its summit. This describes just one of many types of volcano, and the features of volcanoes are much more complicated. The structure and behavior of volcanoes depends on a number of factors. Some volcanoes have rugged peaks formed by lava domes rather than a summit crater, whereas others present landscape features such as massive plateaus. Vents that issue volcanic material (lava, which is what magma is called once it has escaped to the surface, and ash) and gases (mainly steam and magmatic gases) can be located anywhere on the landform. Many of these vents give rise to smaller cones such as Puʻu ʻŌʻō on a flank of Hawaii's Kīlauea.
Lakagigar fissure vent in Iceland, source of the major world climate alteration of 1783-84.
Skjaldbreiður, a shield volcano whose name means "broad shield"
January 2009 image of the rhyolitic lava dome of Chaitén Volcano, southern Chile during its 2008-2009 eruption.
Holocene cinder cone volcano on State Highway 18 near Veyo, Utah.
Mayon, near perfect stratovolcano in the Philippines.
The Lake Toba volcano created a caldera 100 km long
Herðubreið, one of the tuyas in Iceland
Mud volcano on Taman Peninsular, Russia
Other types of volcano include cryovolcanoes (or ice volcanoes), particularly on some moons of Jupiter, Saturn and Neptune; and mud volcanoes, which are formations often not associated with known magmatic activity. Active mud volcanoes tend to involve temperatures much lower than those of igneous volcanoes, except when a mud volcano is actually a vent of an igneous volcano.

Fissure vents

Volcanic fissure vents are flat, linear cracks through which lava emerges.

Shield volcanoes

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, but not generally explode catastrophically. Since low-viscosity magma 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

Lava domes are built by slow eruptions of highly viscous lavas. They are sometimes formed within the crater of a previous volcanic eruption (as in Mount Saint Helens), but can also form independently, as in the case of Lassen Peak. Like stratovolcanoes, they can produce violent, explosive eruptions, but their lavas generally do not flow far from the originating vent.

Cryptodomes

Cryptodomes are formed when viscous lava forces its way up and causes a bulge. The 1980 eruption of Mount St. Helens was an example. Lava was under great pressure and forced a bulge in the mountain, which was unstable and slid down the North side.

Volcanic cones (cinder cones)

Volcanic cones or cinder cones are the result from eruptions that erupt 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 meters high. Most cinder cones erupt only once. 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 is a volcanic field of over 60 cinder cones.

Stratovolcanoes (composite volcanoes)

Stratovolcanoes or composite volcanoes are tall conical mountains composed of lava flows and other ejecta in alternate layers, the strata that give rise to the name. Stratovolcanoes are also known as composite volcanoes, created from several structures during different kinds of eruptions. Strato/composite volcanoes are made of cinders, ash and lava. Cinders and ash pile on top of each other, lava flows on top of the ash, where it cools and hardens, and then the process begins again. Classic examples include Mt. Fuji in Japan, Mayon Volcano in the Philippines, and Mount Vesuvius and Stromboli in Italy. In recorded history, explosive eruptions by stratovolcanoes have posed the greatest hazard to civilizations.[citation needed]

Supervolcanoes

A supervolcano is a large volcano that usually has a large caldera and can potentially produce devastation on an enormous, sometimes continental, scale. Such eruptions would be able to cause severe cooling of global temperatures for many years afterwards because of the huge volumes of sulfur and ash erupted. They are the most dangerous type of volcano. Examples include Yellowstone Caldera in Yellowstone National Park and Valles Caldera in New Mexico (both western United States), Lake Taupo in New Zealand, Lake Toba in Sumatra, Indonesia and Ngorogoro Crater in Tanzania. Supervolcanoes are hard to identify centuries later, given the enormous areas they cover. Large igneous provinces are also considered supervolcanoes because of the vast amount of basalt lava erupted, but are non-explosive.

Submarine volcanoes

Submarine volcanoes are common features on the ocean floor. Some are active and, in shallow water, disclose their presence by blasting steam and rocky debris high above the surface of the sea. Many others lie at such great depths that the tremendous weight of the water above them prevents the explosive release of steam and gases, although they can be detected by hydrophones and discoloration of water because of volcanic gases. Pumice rafts may also appear. Even large submarine eruptions may not disturb the ocean surface. Because of the rapid cooling effect of water as compared to air, and increased buoyancy, submarine volcanoes often form rather steep pillars over their volcanic vents as compared to above-surface volcanoes. They may become so large that they break the ocean surface as new islands. Pillow lava is a common eruptive product of submarine volcanoes. Hydrothermal vents are common near these volcanoes, and some support peculiar ecosystems based on dissolved minerals.

Subglacial volcanoes

Subglacial volcanoes develop underneath icecaps. They are made up of flat lava which flows at the top of extensive pillow lavas and palagonite. When the icecap melts, the lavas on the top collapse, leaving a flat-topped mountain. Then, the pillow lavas also collapse, giving an angle of 37.5 degrees[citation needed]. These volcanoes are also called table mountains, tuyas or (uncommonly) mobergs. Very good examples of this type of volcano can be seen in Iceland, however, there are also tuyas in British Columbia. The origin of the term comes from Tuya Butte, which 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 analyzed 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 the boundary with the Yukon Territory.

Mud volcanoes

Mud volcanoes or mud domes are formations created by geo-excreted liquids and gases, although there are several different processes which may cause such activity. The largest structures are 10 kilometers in diameter and reach 700 meters high.

Erupted material

Pāhoehoe Lava flow at Hawaii (island). The picture shows few overflows of a main lava channel.
The Stromboli volcano off the coast of Sicily has erupted continuously for thousands of years, giving rise to the term strombolian eruption ejecting lava bombs
. Mafic basalt flow created the Deccan Traps near Matheran, east of Mumbai, one of the largest volcanic features on earth.

Lava composition

Another way of classifying volcanoes is by the composition of material erupted (lava), since this affects the shape of the volcano. Lava can be broadly classified into 4 different compositions (Cas & Wright, 1987):
  • If the erupted magma contains a high percentage (>63%) of silica, the lava is called felsic.
    • Felsic lavas (dacites or rhyolites) tend to be highly viscous (not very fluid) and are erupted as domes or short, stubby flows. Viscous lavas tend to form stratovolcanoes or lava domes. Lassen Peak in California is an example of a volcano formed from felsic lava and is actually a large lava dome.
    • Because siliceous magmas are so viscous, they tend to trap volatiles (gases) that are present, which cause the magma to erupt catastrophically, eventually forming stratovolcanoes. Pyroclastic flows (ignimbrites) are highly hazardous products of such volcanoes, since they are composed of molten volcanic ash too heavy to go up into the atmosphere, so they hug the volcano's slopes and travel far from their vents during large eruptions. Temperatures as high as 1,200 °C are known to occur in pyroclastic flows, which will incinerate everything flammable in their path and thick layers of hot pyroclastic flow deposits can be laid down, often up to many meters thick. Alaska's Valley of Ten Thousand Smokes, formed by the eruption of Novarupta near Katmai in 1912, is an example of a thick pyroclastic flow or ignimbrite deposit. Volcanic ash that is light enough to be erupted high into the Earth's atmosphere may travel many kilometres before it falls back to ground as a tuff.
  • If the erupted magma contains 52–63% silica, the lava is of intermediate composition.
    • These "andesitic" volcanoes generally only occur above subduction zones (e.g. Mount Merapi in Indonesia).
    • Andesitic lava is typically formed at convergent boundary margins of tectonic plates, by several processes:
      • Hydration melting of peridotite and fractional crystallization
      • Melting of subducted slab containing sediments
      • Magma mixing between felsic rhyolitic and mafic basaltic magmas in an intermediate reservoir prior to emplacement or lava flow.
  • If the erupted magma contains <52% and >45% silica, the lava is called mafic (because it contains higher percentages of magnesium (Mg) and iron (Fe)) or basaltic. These lavas are usually much less viscous than rhyolitic lavas, depending on their eruption temperature; they also tend to be hotter than felsic lavas. Mafic lavas occur in a wide range of settings:
  • Some erupted magmas contain <=45% silica and produce ultramafic lava. Ultramafic flows, also known as komatiites, are very rare; indeed, very few have been erupted at the Earth's surface since the Proterozoic, when the planet's heat flow was higher. They are (or were) the hottest lavas, and probably more fluid than common mafic lavas.

Lava texture

Two types of lava are named according to the surface texture: ʻAʻa (pronounced [ˈʔaʔa]) and pāhoehoe ([paːˈho.eˈho.e]), both words having Hawaiian origins. ʻAʻa is characterized by a rough, clinkery surface and is the typical texture of viscous lava flows. However, even basaltic or mafic flows can be erupted as ʻaʻa flows, particularly if the eruption rate is high and the slope is steep.
Pāhoehoe is characterized by its smooth and often ropey or wrinkly surface and is generally formed from more fluid lava flows. Usually, only mafic flows will erupt as pāhoehoe, since they often erupt at higher temperatures or have the proper chemical make-up to allow them to flow with greater fluidity.

Volcanic activity

Damavand, highest volcano in Asia, is a potentially active volcano with fumaroles and solfatara near its summit.
Shiprock, the eroded remnant of the throat of an extinct volcano.
Map of volcanoes
Fourpeaked volcano, Alaska, in September 2007, after being thought extinct for over 10,000 years.

Scientific classification of volcanoes

Philippine Institute of Volcanology and Seismology provides a scientific classification system for volcanoes.[2]
Active - Eruption in historic times - Historical record - 500 years - C14 dating - 10,000 years - Local seismic activity - Oral / folkloric history
Potentially Active - Solfataras / Fumaroles - Geologically young (possibly erupted < 10,000 years and for calderas and large systems - possibly < 25,000 years). - Young-looking geomorphology (thin soil cover/sparse vegetation; low degree of erosion and dissection; young vent featuresl; +/- vegetation cover). - Suspected seismic activity. - Documented local ground deformation - Geochemical indicators of magmatic involvement. - Geophysical proof of magma bodies. - Strong connection with subduction zones and external tectonic settings.
Inactive No record of eruption and its form is beginning to change by the agents of weathering and erosion via formation of deep and long gullies.

Popular classification of volcanoes

Active

A popular way of classifying magmatic volcanoes is by their frequency of eruption, with those that erupt regularly called active, those that have erupted in historical times but are now quiet called dormant, and those that have not erupted in historical times called extinct. However, these popular classifications—extinct in particular—are practically meaningless to scientists. They use classifications which refer to a particular volcano's formative and eruptive processes and resulting shapes, which was explained above.
There is no real consensus among volcanologists on how to define an "active" volcano. The lifespan of a volcano can vary from months to several million years, making such a distinction sometimes meaningless when compared to the lifespans of humans or even civilizations. For example, many of Earth's volcanoes have erupted dozens of times in the past few thousand years but are not currently showing signs of eruption. Given the long lifespan of such volcanoes, they are very active. By human lifespans, however, they are not.
Scientists usually consider a volcano to be erupting or likely to erupt if it is currently erupting, or showing signs of unrest such as unusual earthquake activity or significant new gas emissions. Most scientists consider a volcano active if it has erupted in holocene times. Historic times is another timeframe for active. But it is important to note that the span of recorded history differs from region to region. In China and the Mediterranean, recorded history reaches back more than 3,000 years but in the Pacific Northwest of the United States and Canada, it reaches back less than 300 years, and in Hawaii and New Zealand, only around 200 years. The Smithsonian Global Volcanism Program's definition of active is having erupted within the last 10,000 years (the 'holocene' period).

Extinct

Extinct volcanoes are those that scientists consider unlikely to erupt again, because the volcano no longer has a lava supply. Examples of extinct volcanoes are many volcanoes on the Hawaiian Islands in the U.S. (extinct because the Hawaii hotspot is centered near the Big Island), and Paricutin, which is monogenetic. Otherwise, whether a volcano is truly extinct is often difficult to determine. Since "supervolcano" calderas can have eruptive lifespans sometimes measured in millions of years, a caldera that has not produced an eruption in tens of thousands of years is likely to be considered dormant instead of extinct. For example, the Yellowstone Caldera in Yellowstone National Park is at least 2 million years old and hasn't erupted violently for approximately 640,000 years, although there has been some minor activity relatively recently, with hydrothermal eruptions less than 10,000 years ago and lava flows about 70,000 years ago. For this reason, scientists do not consider the Yellowstone Caldera extinct. In fact, because the caldera has frequent earthquakes, a very active geothermal system (i.e. the entirety of the geothermal activity found in Yellowstone National Park), and rapid rates of ground uplift, many scientists consider it to be an active volcano.

Dormant

It is difficult to distinguish an extinct volcano from a dormant one. Volcanoes are often considered to be extinct if there are no written records of its activity. Nevertheless volcanoes may remain dormant for a long period of time, and it is not uncommon for a so-called "extinct" volcano to erupt again. Vesuvius was thought to be extinct before its famous eruption of AD 79, which destroyed the towns of Herculaneum and Pompeii. More recently, the long-dormant Soufrière Hills volcano on the island of Montserrat was thought to be extinct before activity resumed in 1995. Another recent example is Fourpeaked Mountain in Alaska, which, prior to its eruption in September 2006, had not erupted since before 8000 BC and was long thought to be extinct.

Notable volcanoes

Koryaksky volcano towering over Avacha Bay on Kamchatka Peninsula, Far Eastern Russia.
The 16 current Decade Volcanoes are:

Effects of volcanoes

Volcanic "injection"
Solar radiation reduction from volcanic eruptions
Sulfur dioxide emissions by volcanoes.
Average concentration of sulfur dioxide over the Sierra Negra Volcano (Galapagos Islands) from October 23–November 1, 2005
There are many different types of volcanic eruptions and associated activity: phreatic eruptions (steam-generated eruptions), explosive eruption of high-silica lava (e.g., rhyolite), effusive eruption of low-silica lava (e.g., basalt), pyroclastic flows, lahars (debris flow) and carbon dioxide emission. All of these activities can pose a hazard to humans. Earthquakes, hot springs, fumaroles, mud pots and geysers often accompany volcanic activity.
The concentrations of different volcanic gases can vary considerably from one volcano to the next. Water vapor 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.
Large, explosive volcanic eruptions inject water vapor (H2O), carbon dioxide (CO2), sulfur dioxide (SO2), hydrogen chloride (HCl), hydrogen fluoride (HF) and ash (pulverized rock and pumice) into the stratosphere to heights of 16–32 kilometres (10–20 mi) above the Earth's surface. The most significant impacts from these injections come from the conversion of sulfur dioxide to sulfuric acid (H2SO4), which condenses rapidly in the stratosphere to form fine sulfate aerosols. The aerosols increase the Earth's albedo—its reflection of radiation from the Sun back into space - and thus cool the Earth's lower atmosphere or troposphere; however, they also absorb heat radiated up from the Earth, thereby warming the stratosphere. Several eruptions during the past century have caused a decline in the average temperature at the Earth's surface of up to half a degree (Fahrenheit scale) for periods of one to three years — sulfur dioxide from the eruption of Huaynaputina probably caused the Russian famine of 1601 - 1603. The sulfate aerosols also promote complex chemical reactions on their surfaces that alter chlorine and nitrogen chemical species in the stratosphere. This effect, together with increased stratospheric chlorine levels from chlorofluorocarbon pollution, generates chlorine monoxide (ClO), which destroys ozone (O3). As the aerosols grow and coagulate, they settle down into the upper troposphere where they serve as nuclei for cirrus clouds and further modify the Earth's radiation balance. Most of the hydrogen chloride (HCl) and hydrogen fluoride (HF) are dissolved in water droplets in the eruption cloud and quickly fall to the ground as acid rain. The injected ash also falls rapidly from the stratosphere; most of it is removed within several days to a few weeks. Finally, explosive volcanic eruptions release the greenhouse gas carbon dioxide and thus provide a deep source of carbon for biogeochemical cycles.
Rainbow and volcanic ash with sulfur dioxide emissions from Halema`uma`u vent.
Gas emissions from volcanoes are a natural contributor to acid rain. Volcanic activity releases about 130 to 230 teragrams (145 million to 255 million short tons) of carbon dioxide each year.[3] Volcanic eruptions may inject aerosols into the Earth's atmosphere. Large injections may cause visual effects such as unusually colorful sunsets and affect global climate mainly by cooling it. Volcanic eruptions also provide the benefit of adding nutrients to soil through the weathering process of volcanic rocks. These fertile soils assist the growth of plants and various crops. Volcanic eruptions can also create new islands, as the magma cools and solidifies upon contact with the water.

Volcanoes on other planetary bodies

Olympus Mons (Latin, "Mount Olympus") is the tallest known mountain in our solar system, located on the planet Mars.
The Earth's Moon has no large volcanoes and no current volcanic activity, although recent evidence suggests it may still possess a partially molten core.[4] However, the Moon does have many volcanic features such as maria (the darker patches seen on the moon), rilles and domes.
The planet Venus has a surface that is 90% basalt, indicating that volcanism played a major role in shaping its surface. The planet may have had a major global resurfacing event about 500 million years ago,[5] from what scientists can tell from the density of impact craters on the surface. Lava flows are widespread and forms of volcanism not present on Earth occur as well. Changes in the planet's atmosphere and observations of lightning, have been attributed to ongoing volcanic eruptions, although there is no confirmation of whether or not Venus is still volcanically active. However, radar sounding by the Magellan probe revealed evidence for comparatively recent volcanic activity at Venus's highest volcano Maat Mons, in the form of ash flows near the summit and on the northern flank.
There are several extinct volcanoes on Mars, four of which are vast shield volcanoes far bigger than any on Earth. They include Arsia Mons, Ascraeus Mons, Hecates Tholus, Olympus Mons, and Pavonis Mons. These volcanoes have been extinct for many millions of years,[6] but the European Mars Express spacecraft has found evidence that volcanic activity may have occurred on Mars in the recent past as well.[6]
The Tvashtar volcano erupts a plume 330 km (205 mi) above the surface of Jupiter's moon Io.
Jupiter's moon Io is the most volcanically active object in the solar system because of tidal interaction with Jupiter. It is covered with volcanoes that erupt sulfur, sulfur dioxide and silicate rock, and as a result, Io is constantly being resurfaced. Its lavas are the hottest known anywhere in the solar system, with temperatures exceeding 1,800 K (1,500 °C). In February 2001, the largest recorded volcanic eruptions in the solar system occurred on Io.[7] Europa, the smallest of Jupiter's Galilean moons, also appears to have an active volcanic system, except that its volcanic activity is entirely in the form of water, which freezes into ice on the frigid surface. This process is known as cryovolcanism, and is apparently most common on the moons of the outer planets of the solar system.
In 1989 the Voyager 2 spacecraft observed cryovolcanoes (ice volcanoes) on Triton, a moon of Neptune, and in 2005 the Cassini-Huygens probe photographed fountains of frozen particles erupting from Enceladus, a moon of Saturn.[8] The ejecta may be composed of water, liquid nitrogen, dust, or methane compounds. Cassini-Huygens also found evidence of a methane-spewing cryovolcano on the Saturnian moon Titan, which is believed to be a significant source of the methane found in its atmosphere.[9] It is theorized that cryovolcanism may also be present on the Kuiper Belt Object Quaoar.
A 2010 study of the exoplanet COROT-7b, which was detected by transit in 2009, studied that tidal heating from the host star very close to the planet and neighboring planets could generate intense volcanic activity similar to Io.[10]

In culture

Past beliefs

Many ancient accounts ascribe volcanic eruptions to supernatural causes, such as the actions of gods or demigods. To the ancient Greeks, volcanoes' capricious power could only be explained as acts of the gods, while 16th/17th-century German astronomer Johannes Kepler believed they were ducts for the Earth's tears. [11] One early idea counter to this was proposed by Jesuit Athanasius Kircher (1602–1680), who witnessed eruptions of Mount Etna and Stromboli, then visited the crater of Vesuvius and published his view of an Earth with a central fire connected to numerous others caused by the burning of sulfur, bitumen and coal.
Various explanations were proposed for volcano behavior before the modern understanding of the Earth's mantle structure as a semisolid material was developed. For decades after awareness that compression and radioactive materials may be heat sources, their contributions were specifically discounted. Volcanic action was often attributed to chemical reactions and a thin layer of molten rock near the surface.

Panoramas

Black Rock Volcano an extinct cinder cone near Fillmore, Utah.
Vulcano island with the north coast of Sicily in the background.
Remote Binubulauan in Kalinga province, central northern Luzon, Philippines, April 2009

See also

Lists
Specific locations
People

Further reading

  • Marti, Joan and Ernst, Gerald. (2005). Volcanoes and the Environment. Cambridge University Press. ISBN 0-521-59254-2. 
  • Macdonald, Gordon A., and Agatin T. Abbott. (1970). Volcanoes in the Sea. University of Hawaii Press, Honolulu. 441 p.
  • Ollier, Cliff. (1988). Volcanoes. Basil Blackwell, Oxford, UK, ISBN 0-631-15664-X (hardback), ISBN 0-631-15977-0 (paperback).
  • Haraldur Sigurðsson, ed. (1999) Encyclopedia of Volcanoes. Academic Press. ISBN 0-12-643140-X. This is a reference aimed at geologists, but many articles are accessible to non-professionals.
  • Cas, R.A.F. and J.V. Wright, 1987. Volcanic Successions. Unwin Hyman Inc. 528p. ISBN 0-04-552022-4

References

  1. ^ Douglas Harper (November 2001). "Volcano". Online Etymology Dictionary. http://www.etymonline.com/index.php?term=volcano. Retrieved 2009-06-11. 
  2. ^ [1]
  3. ^ "Volcanic Gases and Their Effects" (HTML). U.S. Geological Survey. http://volcanoes.usgs.gov/Hazards/What/VolGas/volgas.html. Retrieved 2007-06-16. 
  4. ^ M. A. Wieczorek, B. L. Jolliff, A. Khan, M. E. Pritchard, B. P. Weiss, J. G. Williams, L. L. Hood, K. Righter, C. R. Neal, C. K. Shearer, I. S. McCallum, S. Tompkins, B. R. Hawke, C. Peterson, J, J. Gillis, B. Bussey (2006). "The Constitution and Structure of the Lunar Interior". Reviews in Mineralogy and Geochemistry 60 (1): 221–364. doi:10.2138/rmg.2006.60.3. 
  5. ^ D.L. Bindschadler (1995). "Magellan: A new view of Venus' geology and geophysics". American Geophysical Union. http://www.agu.org/journals/rg/rg9504S/95RG00281/index.html. Retrieved 2006-09-04. 
  6. ^ a b "Glacial, volcanic and fluvial activity on Mars: latest images". European Space Agency. 2005-02-25. http://www.esa.int/esaMI/Mars_Express/SEMLF6D3M5E_0.html. Retrieved 2006-08-17. 
  7. ^ Exceptionally Bright Eruption on lo Rivals Largest in Solar System, Nov. 13, 2002
  8. ^ PPARC, Cassini Finds an Atmosphere on Saturn's Moon Enceladus
  9. ^ NewScientist, Hydrocarbon volcano discovered on Titan, June 8, 2005
  10. ^ Jaggard, Victoria (2010-02-05). ""Super Earth" May Really Be New Planet Type: Super-Io". National Geographic web site daily news. National Geographic Society. http://news.nationalgeographic.com/news/2010/02/100205-new-type-planet-corot-7b-io/. Retrieved 2010-03-11. 
  11. ^ Micheal Williams (11-2007). "Hearts of fire". Morning Calm (Korean Air Lines Co., Ltd.) (11-2007): 6. 

External links



Travel guide

Up to date as of January 14, 2010

From Wikitravel

This article is a travel topic.
.Volcanoes come in all sorts of shapes and sizes.^ These different types of volcanoes come in different shapes and erupt in various ways.
  • Volcanoes | Universe Today 3 February 2010 19:019 UTC www.universetoday.com [Source type: FILTERED WITH BAYES]

.Although the name evokes images of the conical mountain spewing ash and lava, such events are rare though often newsworthy, and are probably best seen on the TV news rather than witnessed up close and in person.^ The recent flows on the pali show up much lighter in color than the older lava beneath.
  • Kilauea Volcano Eruption Update & Information 3 February 2010 19:019 UTC www.volcanogallery.com [Source type: FILTERED WITH BAYES]

^ For instance, as when Jaye didnt see the ash tower, a post-production effect of a huge tower of lava is shown fountaining up from the La Brea Tar Pits.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

^ DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
  • Kilauea Volcano Eruption Update & Information 3 February 2010 19:019 UTC www.volcanogallery.com [Source type: FILTERED WITH BAYES]

.However, many volcanoes around the world are tourist attractions in their own right and are worth a visit, so one can appreciate the awesome power of nature in person.^ A few other Squidoo Members have visited volcanoes and shared their own photos and memories!
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Here's some links to other web pages sharing volcano myths -- "geomythology" -- from around the world.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ A s of the 1st of January, Mount Etna is one of the most active volcanoes in the world and is in an almost constant state of activity.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

Mts. Bromo and Semeru in action, Java, Indonesia
Mts. Bromo and Semeru in action, Java, Indonesia

Understand

.Some of the largest volcanoes on earth are not recognisable as such.^ Chile's chain of some 2,000 volcanoes is the world's second-largest after Indonesia's.

^ These are some of the most active -- and peaceful -- volcanoes on Earth.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

.For example, Yellowstone in the United States, Toba in Indonesia, and Taupo in New Zealand are known as super-volcanoes.^ New Zealand Volcano Cams This page has links to cams for several of New Zealand's volcanoes, plus current seismograph readings.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ They are now known as Novy Tolbachik or New Tolbachik volcano.
  • Kamchatkan volcanoes 3 February 2010 19:019 UTC maurice.strahlen.org [Source type: FILTERED WITH BAYES]

^ Latest news of supervolcano YELLOWSTONE CALDERA in Wyoming in the United States in the "Restless Volcanoes Status Report" section.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.They are generally in the form of large calderas, which are giant volcanic depressions formed either by large explosive eruptions or quiet long-term drainage of magma, and they often have associated lava flows or domes.^ Derrick Cave Lava Tube: 19 Near the main vent, much of the lava flowed through a narrow, open gutter and formed a large, sinuous, well-developed lava tube, Derrick Cave.
  • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

^ A pyroclastic-surge and pumice layer that was considered to originate from the eruption that formed the elliptical 2.5 x 4 km wide summit caldera was dated at about 9400 years ago.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

^ Overlapping shield volcanoes that formed around major vents extruded a complex of basaltic lava flows in some places.
  • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

.Most supervolcanoes are explosive in origin and have undergone unimaginably huge eruptions in the geologic past.^ Tungurahua has had at least seventeen eruptions in historical times, its most recent occurring in 1944 when it erupted explosively from its central crater.

^ Includes eruption summaries, reports, data and references to most volcanoes that have been active over the past 11,000 years.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, which is located immediately south of Karymsky volcano.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.However, it is important to note that such volcanoes have erupted violently very infrequently, usually only once every 100,000-800,000 years.^ Volcano erupts after 9000 years .
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Chile's Chaiten Volcano, which erupted spectacularly last year, spewed a vast cloud of ash on Thursday in what appeared to be a partial collapse of its cone.

^ The volcano has been erupting in a more destructive manner than usual for the past year, and producing high sulfur dioxide emissions for at least six months.

Hence, there is no reason to worry that Yellowstone, for example, will explode within your lifetime! .Many are so big that, for many years, geologists did not appreciate that these features were volcanoes in their own rights.^ Stromboli Online This multi-lingual website actually covers many more volcanoes than Stromboli, and features some spectacular photography.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ By construction and examining the model, students will obtain a greater appreciation of the relationship between the internal structure of the volcano and its exterior shape and features.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ Many structural features in these flows are similar to structural features in flows that compose most of the Pliocene and younger basaltic-rock aquifers.
  • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

.Compared to these, the currently active volcanoes on earth are relatively quite small!^ These are some of the most active -- and peaceful -- volcanoes on Earth.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ They then synthesize their knowledge by creating and presenting reports about currently active volcanoes around the world."
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ EARTHS ACTIVE VOLCANOES http://www.geo.mtu.edu/volcanoes/world.html Lists Earths active volcanoes by geographical region.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

.Although there are literally hundreds of active volcanoes around the world, there are many more that are extinct.^ Imagine being in an active volcano, and standing literally three feet away from the main pool of lava.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

^ Lava has oozed from a new location on Kilauea, one of the worlds most active volcanoes, scientists said.

^ Erebus, the world's southernmost historically active volcano, overlooks the McMurdo research station on Ross Island.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.One can still appreciate the awesome power of nature from such places without the hazards that go with active volcanoes.^ It is also one of the most active volcanoes in the Aleutians.

^ The volcano still poses a hazard to the local population with ashfall and acid rain affecting food crops and drinking water.

^ T he eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.A volcano is defined as active if it has erupted within the last 10,000 years (less than a second in geological time!^ Volcano erupts after 9000 years .
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Io, Jupiter's Volcanic Moon This moon of Jupiter caught everyone by surprise when the space probe Voyager passed by: it had active, erupting volcanoes!
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Much of its > 530,000 year history overlapped with eruptions of the deeply dissected Piton des Neiges shield volcano to the NW. Three calderas formed at about 250,000, 65,000, and less than 5000 years ago by progressive eastward slumping of the volcano.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

), according to the .Smithsonian Global Volcanism Program, the major volcano monitoring organization based in Washington, DC. One that is active but not currently erupting is considered dormant.^ It is also one of the most active volcanoes in the Aleutians.

^ Io, Jupiter's Volcanic Moon This moon of Jupiter caught everyone by surprise when the space probe Voyager passed by: it had active, erupting volcanoes!
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ N evado del Huila, the highest active volcano in Colombia, is an elongated N-S-trending volcanic chain mantled by a glacier icecap.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.Any volcano that has not erupted for more than 10,000 years and often, but not always, lacking geothermal heat and activity, may be considered extinct.^ Mount Jefferson last erupted more than 20,000 years ago.
  • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

^ Volcano erupts after 9000 years .
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Some extinct volcanoes are nothing more than a small mountain, similar in appearance to the surrounding mountains.
  • Kamchatkan volcanoes 3 February 2010 19:019 UTC maurice.strahlen.org [Source type: FILTERED WITH BAYES]

.(But this is problematic when dealing with supervolcanoes because of their long and slow cycles of activity, and not to mention that some supposedly extinct volcanoes can come back to life).^ Some extinct volcanoes are nothing more than a small mountain, similar in appearance to the surrounding mountains.
  • Kamchatkan volcanoes 3 February 2010 19:019 UTC maurice.strahlen.org [Source type: FILTERED WITH BAYES]

^ After this activity the volcano went back to steady levels.

^ Because often several volcanoes can be found in a single complex I put some together under a single entry.
  • Kamchatkan volcanoes 3 February 2010 19:019 UTC maurice.strahlen.org [Source type: FILTERED WITH BAYES]

Geothermal Areas

.Throughout volcanic areas of the world, one may also encounter geothermal areas.^ It is popular with mountaineers and is seen as having one of the world's most perfect volcanic cone shapes.

These places are often, but not always, associated with volcanic activity. .Hot springs, geysers, mud pools and fumaroles (steam/gas vents) are common features in geothermal areas, and can be scenic and hot springs can be great places to take a dip in.^ The temperature of the fumarols vary from 50 to 900C. Apart from the common fumarolic gasses elements measured in the gas include Cu, Pb, Mo, Zn, Bi and Ag.
  • Kamchatkan volcanoes 3 February 2010 19:019 UTC maurice.strahlen.org [Source type: FILTERED WITH BAYES]

^ Yellowstone Volcano Observatory Roaring geysers and boiling pools of hot mud betray the sleeping giant beneath: an ancient volcano that lies under nearly half of the state of Wyomoing.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Multnomah Falls offers one of the best places in the Columbia River Gorge National Scenic Area to study geology exposed by floods.
  • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

Countries such as Japan and Iceland are especially famous for hot spring baths. Geothermal areas are also an environmentally friendly source of energy, and Iceland takes advantage of this very well.
.Yellowstone National Park is probably the best known example of a geothermal area, as molten magma lies not far beneath its 640,000 year-old caldera.^ Yellowstone National Park First established as a National Park in 1872, Yellowstone remains America's best-known National Park for its geothermal features, array of wildlife and stunning scenery.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Santa Barbara Island lies far south of the other four park islands.
  • Webchat 23 September 2009 4:43 UTC www.rain.org [Source type: General]

^ Lake Toba is a large caldera formed by volcanic and tectonic processes, and was the site of the world's most recent supervolcano 74,000 years ago.

.New Zealand, with its volcanoes in the North Island, is also known for extensive geothermal areas.^ They are now known as Novy Tolbachik or New Tolbachik volcano.
  • Kamchatkan volcanoes 3 February 2010 19:019 UTC maurice.strahlen.org [Source type: FILTERED WITH BAYES]

^ Decade Volcanoes Website A site giving news, updates, online tours and photos for several well-known volcanoes.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ The current lake volume is large enough that it will influence the next phase of eruptive activity from the volcano and result in a new hazard to people visiting the island.

Stay Safe

.If you are intending to venture into an area containing a highly active volcano, be aware that you are entering a potential hazard zone. Depending on the level of activity, the hazard zone may extend for several dozen kilometres, and there is the serious potential for pyroclastic flows and flying volcanic bombs, which are larger pieces of rocks thrown up by eruptions.^ He notes that examining rocks can tell you when the volcano was last active.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

^ There is potential for a significant eruption.

^ "What do you think the odds are against an eruption up there?
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

.Volcanic bombs can be up to the size of a soccer ball or even larger - enough to kill an unprotected person.^ Nope, hes a Capitalist, and thats enough, even if hes had roughly forty seconds of screentime up til now.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

.Pyroclastic flows are clouds of red-hot ash and other volcanic debris that rush downslope from their source vents.^ A hot, heavy ash cloud rolls above and races ahead of the flow.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Earlier, Hendrasto said that historically the volcano's eruptions have involved ash, smoke and small pieces of volcanic debris.

^ Glowing streaks of red from the pyroclastic flows have created nighttime spectacles visible across much of the island.

.They are some of the most dangerous parts of volcanic eruptions, as the temperature inside a pyroclastic flow can reach 400-700°C (~750-1300°F) and can reach speeds of up to 150 km/h (93 mph).^ Pyroclastic flows or surges are extremely dangerous.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Temperatures inside range from 200 to 700 degrees C. At night they sometimes glow red, hence the old name "glowing clouds."
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Pyroclastic flows also occurred to the northwest approx 2 km down Tyers Ghaut on the 25th of January.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.Obviously, this means they can literally incinerate everything flammable in their path and then bury the area in hot ash.^ They bury, shatter, or carry away anything in their path.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

.Other associated hazards like volcanic ashfall and lahars (volcanic mudflows) can extend for hundreds of kilometres more.^ South Sister, Broken Top, Mount Jefferson, and several other peaks have a more complex volcanic history.
  • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

^ When moving, a lahar looks like a mass of wet concrete that carries rock debris ranging in size from clay to boulders more than 10 m in diameter.

^ Sections include: Eruptive History, Geological History, Geological Evolution, Volcanic Hazards, and more.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

.Also, volcanic ash tends to stop aircraft and vehicle engines, so transportation in the area may be restricted or disrupted.^ Jones wants NPG, who I guess runs the citys public transportation, to temporarily stop running the subway trains in this area.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

^ Volcanic ash is falling and combining with torrential rain and high winds in the area.

.Public safety authorities may order hazard areas evacuated and would normally prefer that the casual tourist stay well away.^ Visitors must stay well away from the volcanic steam clouds which contain hydrochloric acid and glass particles.
  • Kilauea Volcano Eruption Update & Information 3 February 2010 19:019 UTC www.volcanogallery.com [Source type: FILTERED WITH BAYES]

^ Authorities evacuated about 100 people from the area.

^ Authorities ordered 116,000 people living along the fertile slopes to evacuate, but many have refused, saying they need to tend to their crops and animals.

.Unless you have some very genuine reasons for going to these places, the best advice is to stay away and watch it from the safety of your home on the TV news.^ Unless youre really going to surprise us by either killing off Brosnan or his new love (Linda Hamilton, presumably, as shes the female lead) or actually lending some depth to the characterizations, well, wed dont give a rats ass.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

^ Don't forget the timezone; it will be night-time in some of these places.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Not only will you have to convince people to evacuate their homes, but you will also be putting your life in danger as well."
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

.When active volcanoes are not erupting (in other words, simply dormant), many of them can be approached reasonably closely in safety.^ Redoubt and many other volcanoes.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Io, Jupiter's Volcanic Moon This moon of Jupiter caught everyone by surprise when the space probe Voyager passed by: it had active, erupting volcanoes!
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ Stratovolcanoes , also called composite volcanoes , form grand, steep mountains that may remain dormant for long periods before erupting.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

.However, when visiting active volcanic areas, there are still plenty of hazards even in dormant volcanic areas.^ April 2005 deep volcanic = 7 events ; shallow volcanic = 5 events 16 April 2005 deep volcanic = 2 events ; shallow volcanic = 8 events 17 April 2005 deep volcanic = 0 events ; shallow volcanic = 2 events 18 April 2005 deep volcanic = 0 events ; shallow volcanic = 1 events It is still forbidden to visit the summit crater of Anak Krakatau volcano.

.New lava flows may still be very hot for months or even years afterwards and may be only covered with a thin crust of solid rock.^ Only five month later, in may, the river broke through and washed away this locality.
  • Kamchatkan volcanoes 3 February 2010 19:019 UTC maurice.strahlen.org [Source type: FILTERED WITH BAYES]

^ Soon only the driver and NPG are left in the train as the lava flows along under the train.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

^ Last evening, CD officials reported lava continuing to advance and burn forest down the west side of the TEB flows on the pali.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.Old lava flows can be as sharp as broken glass, so wearing a good pair of shoes or hiking boots are a must.^ Much of the cone is mantled by lava flows less than 200 years old.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

^ About 90% of the surface of the basaltic shield volcano is formed of lava flows less than about 1100 years old; 70% of the volcano's surface is younger than 600 years.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

Even geothermal areas can be hazardous. .Many of the hazards encountered in geothermal areas are similar to volcanic hazards, because both arise from similar geological mechanisms.^ Sections include: Eruptive History, Geological History, Geological Evolution, Volcanic Hazards, and more.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ HAZARD ALERT: The lava delta and adjacent areas both inland and out to sea are some of the most hazardous areas on the flow field.
  • Kilauea Volcano Eruption Update & Information 3 February 2010 19:019 UTC www.volcanogallery.com [Source type: FILTERED WITH BAYES]

^ Three well-known areas on the Moon interpreted as important volcanic complexes are: Aristarchus plateau, and the Marius Hills and Rumker Hills (both located in Oceanus Procellarum).
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

.Hot springs and mud pools can be boiling hot, acidic or downright poisonous, hence do not even try to take a dip or approach unless it is absolutely safe to do so.^ Yellowstone Volcano Observatory Roaring geysers and boiling pools of hot mud betray the sleeping giant beneath: an ancient volcano that lies under nearly half of the state of Wyomoing.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ These walls of boiling hot mud have the consistency of concrete and can move at the speed of a freight train, overflowing riverbanks and sweeping away roads and towns.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

^ We cut to two Innocent Young Lovers skinny-dipping in the local hot springs.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

.Geysers are a common feature of major geothermal areas, and can erupt hot water or mud unexpectedly.^ The Norris Back Basin has been closed since July 23 due to the formation of new mud pots, changes in geyser activity and much higher ground temperatures, as hot as 200 degrees in some areas.

^ What looks like a gray river is actually superheated mud and volcanic material mixed with water, and it's boiling hot.
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

.Landslides are also common, as even volcanic rock can become weakened over time with acidic fumes seeping out of fumaroles (steam/gas vents) or hot springs.^ A second vent later opened near the southern summit, piggy-backing its lava and tephra over the previously erupted volcanic rocks.
  • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

^ In contrast to the mostly andesitic Acatenango volcano, eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

^ Increased fumarolic activity is common on the warmest days in the summer when snow melts in the crater and more steam is produced.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

.Noxious gases may come out of vents or similar holes in the ground and may be concentrated in enclosed low-lying spaces such as caves, manholes, and pool enclosures.^ Lava rises from depth at this location, but is normally out of view due to the low shield built over the vent.
  • Kilauea Volcano Eruption Update & Information 3 February 2010 19:019 UTC www.volcanogallery.com [Source type: FILTERED WITH BAYES]

^ "Its coming right up out of the ground itself," he notes in a bewildered fashion, although he doesnt explain exactly where else it would come from.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

.Carbon dioxide, a byproduct of volcanic activity, is notorious for this and can kill swiftly with little or no warning.^ In the last weeks emissions of Sulphur Dioxide, no significant fumarolic activity have generally not been detected.
  • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

^ A volcano erupted Saturday with little warning on a remote Aleutian island, sending residents of a nearby ranch fleeing from falling ash and volcanic rock.

Active Volcanoes

.A selection of some of the more active and/or better known volcanoes in the world today.^ They then synthesize their knowledge by creating and presenting reports about currently active volcanoes around the world."
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ EARTHS ACTIVE VOLCANOES http://www.geo.mtu.edu/volcanoes/world.html Lists Earths active volcanoes by geographical region.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ Your job in this WebQuest is to explore the active volcanoes of the world and discover how these volcanoes are related.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

Some of these can still be explored from up close.
  • Kilimanjaro in Tanzania is Africa's tallest peak at 5895 m (19,340 ft). .It has a series of concentric summit craters apparently less than 10,000 years old and may have last erupted less than 2000 years ago.^ Mount Jefferson last erupted more than 20,000 years ago.
    • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

    ^ Much of its > 530,000 year history overlapped with eruptions of the deeply dissected Piton des Neiges shield volcano to the NW. Three calderas formed at about 250,000, 65,000, and less than 5000 years ago by progressive eastward slumping of the volcano.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    .The name Kilimanjaro means "shining mountain" in Swahili, no doubt due to the once-extensive glaciers which are unfortunately disappearing rapidly each year.
  • Ol Doinyo Lengai ("Mountain of God" in the Masai tongue), in Tanzania, is the only volcano on Earth that erupts natrocarbonatite lava.^ Volcano erupts after 9000 years .
    • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

    ^ The Siskiyou Mountains were not heavily glaciated in the last ice age and served as a refuge for species whose habitat disappeared under tons of continental ice.
    • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

    ^ Basaltic lava erupts at no less than about 1100 degrees C. Basalt is a very fluid lava; it is likely that tongues of lava advanced at an average of 5 kilometers/hour -- faster than most animals can run.
    • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

    This type of lava emerges black, cools to grey, and oxidizes to white.
  • Mount Cameroon The only volcano outside of Europe to have records of an erruption before the Common Era in 5 BC. It remains active today, with its most recent erruption in 2000.

Asia

Indonesia

Mount Semuru erupting in 2004
Mount Semuru erupting in 2004
.With 167 known active volcanoes, Indonesia is the world's most volcanic country by far.^ Come visit the most active Volcano in the World.
  • Kilauea Volcano Eruption Update & Information 3 February 2010 19:019 UTC www.volcanogallery.com [Source type: FILTERED WITH BAYES]

^ It is also one of the most active volcanoes in the Aleutians.

^ Io, Jupiter's Volcanic Moon This moon of Jupiter caught everyone by surprise when the space probe Voyager passed by: it had active, erupting volcanoes!
  • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

Volcano Adventure Indonesia, Sukapura, tel. +62-335-581439 , +62-81319090225, .[1] runs specialist volcano tours all around the country.^ The Laima volcano is part of a chain of around 2,000 in the country [EPA] .

.
  • Mount Bromo in East Java is known for its unreal scenery, especially with Mount Semeru, Indonesia's third highest active volcano nearby.
  • Krakatoa in West Java famously exploded so violently in 1883 that the sound was heard 5,000 km away and global temperatures dipped by over a degree.
  • Mount Batur in Bali is a very accessible active volcano which takes just 2 hours to climb.
  • Mount Rinjani in Lombok is Indonesia's second highest volcano with a stunning crater lake.^ Crater Lake lies inside the top of an ancient volcano known as Mount Mazama.
    • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

    ^ Yellowstone National Park First established as a National Park in 1872, Yellowstone remains America's best-known National Park for its geothermal features, array of wildlife and stunning scenery.
    • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

    ^ N evado del Huila, the highest active volcano in Colombia, is an elongated N-S-trending volcanic chain mantled by a glacier icecap.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    .For much of 2009 the summit of the mountain was closed to the public due to eruptive activity.
  • Mount Tambora in Sumbawa is one for the truly adventurous.^ A s of the 1st of January, Mount Etna is one of the most active volcanoes in the world and is in an almost constant state of activity.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ The present activity in Galeras continues showing a development unstable, similar to the registered one before the occurrence of some of the recent eruptive events.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Due to its history of recent activity and nearby population, Mount Etna has been designated a Decade Volcano by the United Nations.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    .Only about 50 visitors a year make it to this very remote volcano.^ Construction of Meseta volcano dates back to about 230,000 years and continued until the late Pleistocene or early Holocene.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Only about 50 persons live on the sparsely populated island.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ The caldera enclosing Karymsky volcano formed about 7600-7700 radiocarbon years ago; construction of the Karymsky stratovolcano began about 2000 years later.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    In 1814 Tambora was 4,200 metres high. It erupted with such force the following year that 1,400 metres was lost from its top.

Elsewhere

.
  • Mount Aso on the island of Kyushu in Japan, is one of the largest active volcanoes in the world with the largest caldera.
  • Mount Fuji in central Japan near Tokyo, is Japan's highest and most beautiful volcano.^ K liuchevskoi is Kamchatka's highest and most active volcano.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Come visit the most active Volcano in the World.
    • Kilauea Volcano Eruption Update & Information 3 February 2010 19:019 UTC www.volcanogallery.com [Source type: FILTERED WITH BAYES]

    ^ The archipelago nation has the world's highest number of active volcanoes.

    .It is also the most climbed mountain in the world because so many people climb it to view the sunrise from its summit crater.
  • Mayon Volcano, near Legazpi City in the Philippines, described as the world's most perfect volcano cone.^ Satellites can detect volcanoes that are more than 1500 m high because the mass of the submerged mountains causes gravity to pull the water in around them.

    ^ PHILIPPINES - PREPARE FOR IMMEDIATE EVACUATION authorities on Sunday warned residents living near Mount Mayon, as lava flowed past the volcano's six-kilometer permanent danger zone.

    ^ Kilauea Iki was another vent that broke out near the summit of Kilauea Volcano, in a crater right next to the caldera.
    • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

    .Mayon’s last fatal eruption was in 1993.
  • El Teide in Tenerife, is the highest active volcano in the Canary Islands at 3715 m (12,188 ft).^ N evado del Huila, the highest active volcano in Colombia, is an elongated N-S-trending volcanic chain mantled by a glacier icecap.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ The volcano, whose name means "Child of Krakatau," formed in the Sunda Strait close to Java island after Mount Krakatau's legendary eruption in 1883.

    ^ Includes eruption summaries, reports, data and references to most volcanoes that have been active over the past 11,000 years.
    • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

    .A flank vent at El Teide was observed erupting by Christopher Columbus and his crew in 1492.
  • Vesuvius near Naples in Italy is an active (but presently "dormant") volcano.^ Io, Jupiter's Volcanic Moon This moon of Jupiter caught everyone by surprise when the space probe Voyager passed by: it had active, erupting volcanoes!
    • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

    ^ Stratovolcanoes , also called composite volcanoes , form grand, steep mountains that may remain dormant for long periods before erupting.
    • Volcanoes Are Hot Stuff 3 February 2010 19:019 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

    ^ The closest active volcano to the earthquake is Kunlun in Western China, which last erupted in 1951.

    .It has not been smoking since it last erupted in 1944, but it is still very closely monitored because of its seriously hazardous proximity to Naples, which is southern Italy's largest city.
  • Stromboli in the Aeolian Islands of Italy and Mount Etna in Sicily, Italy are two of Italy's most active volcanoes.^ It is also one of the most active volcanoes in the Aleutians.

    ^ Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism, dating back to 1500 BC. Historical lava flows of basaltic composition cover much of the surface of this massive volcano, whose edifice is the highest and most voluminous in Italy.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Chile's Chaiten Volcano, which erupted spectacularly last year, spewed a vast cloud of ash on Thursday in what appeared to be a partial collapse of its cone.

    At 3350 m (10,991 ft), Etna is Europe's highest volcano. .Stromboli has been in near continuous activity since at least the time of the Ancient Greeks and has been billed as the "Lighthouse of the Mediterranean".
  • Nisyros in the Greek Dodecanese islands is mildly active with smoking fumaroles.^ Fumarolic activity continues at the central and SW summit craters.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ A lava lake in the summit crater, active since at least 1921, drained in 1938, at the time of a major flank eruption.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Stromboli, the NE-most of the Aeolian Islands, has lent its name to the frequent mild explosive activity that has characterised its eruptions throughout much of historical time.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    .It is possible to walk into the crater floor for a closer look.
  • Santorini in the Aegean Sea, is probably Greece's most famous volcano because of its eruption that destroyed the Minoan civilization over 3,600 years ago.^ Its most recent eruption was about 1,300 years ago.
    • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

    ^ Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ We use a short cup to hold the baking soda because we are looking at the flows and not at constructing a volcano model.
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    It is still active, for it last erupted in 1950 out of Nea Kameni ("New Burnt" in Greek), an island made up of lava flows in the middle of the caldera bay.
  • Mount St. Helens, in Washington State, USA, is famous for its May 18, 1980 eruption. .Since late 2004, it has been erupting once again, but not nearly as violently - this time, a new lava dome is slowly being extruded in its crater.
  • Popocatepetl, near Mexico City, often has a volcanic plume above its crater which is 5,450m high.^ Mexico's Volcano of Fire, also known as the Colima volcano, is seen in a time exposure photograph during an explosion as lava and hot rocks flow down its sides and lightning flashes over its crater late June 1, 2005.

    ^ A s of the 29th of January, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that activity of the volcano continues: a new viscous lava flow effuses at the lava dome.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ A rhyolitic, 962-m-high obsidian lava dome occupies much of the caldera floor.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    .The name means "smoking mountain" in the native Nahuatl language.
  • Soufriere Hills volcano on Montserrat, previously considered dormant, began erupting again in 1995, forcing the closure of the southern half of the island (including its capital and airport in 1997).^ Latest news of the eruption of volcano SOUFRIERE HILLS on Montserrat in the Caribbean.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ T he complex, dominantly andesitic Soufrière Hills volcano occupies the southern half of the island of Montserrat.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ There is no access to Zone C and only daytime access (0630 hrs to 1730 hrs) to part of Zone B. T he complex, dominantly andesitic Soufrière Hills volcano occupies the southern half of the island of Montserrat.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    .It is still active, though mostly a nuisance seeping lava and spewing ash into the air.
  • Cotopaxi in Ecuador, often misquoted as being the highest volcano in the world ( despite its elevation of 5911 m (19, 393 ft), it does not even make the top ten list of highest active volcanoes - see this list here), is still one of South America's most spectacular volcanoes.
  • Arenal in Costa Rica can be viewed lighting up the night sky with its highly frequent eruptions.
  • Mount Ruapehu, Mount Ngauruhoe and Mount Tongariro in New Zealand's Tongariro National Park.^ Latest news of the eruption of volcano FUEGO in Guatemala.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Aleutian volcano spews ash 50,000 feet into the air .

    ^ T he eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    .Ruapehu, New Zealand's highest volcano, has a crater lake that forms and fills when the volcano is not erupting.
  • White Island, also in New Zealand, is the most active volcano in that country and is a volcanic island in the Bay of Plenty southeast of Auckland.^ K liuchevskoi is Kamchatka's highest and most active volcano.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Sunday, August 10, 2003 New crater lake forms at White Island Volcano...

    ^ It is also one of the most active volcanoes in the Aleutians.

    .Organized tours are operated out to this volcano.
  • Kilauea in the Big Island of Hawaii, has been erupting continuously out of its flank vent, known as Pu'u O'o ("Hill of the O'o bird" in the native Hawai'ian language) since 1983.
  • Mauna Loa, also in Hawaii, is the state's highest historically active volcano and is topped by the Moku'aweoeo Caldera.^ K ilauea volcano, which overlaps the east flank of the massive Mauna Loa shield volcano, has been Hawaii's most active volcano during historical time.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ Update news of the continuing eruption of volcano KILAUEA in Hawaii.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ VOLCANO VILLAGE http://volcanovillage.com/ " Located on the Big Island of Hawaii, 28 miles from Hilo at an elevation of 3700 feet, Volcano Village sits at the entrance to the Hawaii Volcanoes National Park, home of Kilauea and Mauna Loa volcanoes; Kilauea being the most active volcano on the planet.
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    .It is also the largest volcano by volume in the world.^ Chile's chain of some 2,000 volcanoes is the world's second-largest after Indonesia's.

    ^ The earthquake was located about 100 km NE of Manam volcano, the site of the largest eruption in the world in 2004.

    .Don't be fooled by its gentle slopes - with its highest point at 4170m/13,683 ft), the altitude can be hard on inexperienced hikers and its summit is often covered in snow during the winter.
  • Mauna Kea is the highest volcano in Hawaii at 4205 m (13,796 ft), and is pockmarked with cinder cones.^ Many have summit cinder cones.
    • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

    ^ A lower level ash plume covering a large area drifted south at an altitude of 18,000 ft.

    ^ The highest point on the volcano, Paulina Peak with an elevation of 7,984 feet, is about 4,000 feet higher than the terrain surrounding the volcano.
    • CVO Menu - America's Volcanic Past - Oregon 28 January 2010 1:01 UTC vulcan.wr.usgs.gov [Source type: FILTERED WITH BAYES]

    Its high elevation is also a magnet for astronomers with their giant telescope facilities - and even skiers.
  • Hale'akala ("House of the sun" in Hawai'ian), is the tallest volcano on the island of Maui, and is renowned for its erosional crater and the cinder cones nestled inside.

Travel agencies

.The following travel agencies specialize in volcano tourism.^ The Yasur volcano on Tanna Island in the south of the archipelago was "of more concern for tourists and tourism agencies," who visit it frequently, she noted.

  • Volcano Adventure Indonesia, Sukapura, Indonesia, tel. +62-335-581439 , +62-81319090225, [2]. Tours to Mount Bromo and elsewhere in Indonesia.
  • VolcanoDiscovery, Germany, tel. +49-2241-2080175, +30-2107522310, [3]. .This tour operator is specialized on international volcanoes and one of its most important programs are provided for Indonesian volcanoes.^ It is also one of the most active volcanoes in the Aleutians.

    ^ T he eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    ^ It has one of Earth's few long-lived lava lakes and is the most active volcano in Antarctica.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    The tours are trekking & photography tours with small groups and an intensive personal service. .The tours are usually about 7-14 days.
  • Volcano Guide in Indonesia, Tangerang, Indonesia, +62-8111875236, [4].^ Students will participate in a virtual reality tour by the use of my web pages to explore and learn about volcanoes in Mexico."
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    specialist in Volcano Tour and Volcano Expedition also some Jungle Trekking In Indonesia, all of the trip is private tours in Indonesia.
This is a usable article. It has information for getting in as well as some complete entries for restaurants and hotels. An adventurous person could use this article, but please plunge forward and help it grow!

Wikibooks

Up to date as of January 23, 2010

From Wikibooks, the open-content textbooks collection

Hello, reader. You have come to the right place if you wish to learn about volcanoes. .An excellent resource on volcanoes is Wikipedia's article on volcanoes, which will provide interesting information about different kinds of volcanoes.^ This will be like an informational booklet about volcanoes.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ You will learn about three different types of plate boundaries, and what kinds of volcanic activities are associated with each type.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ "In this lesson, students explore first-person accounts of volcanic eruptions throughout time and use the Internet to access second-hand information about volcanoes.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

.You might be curious what a volcano is.^ Take a field trip, view volcanoes in action, and learn what a volcanologist actually does on the job, and see if you might like to become a volcanologist in the future.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ This leads me -- as you might have guessed from the title of this piece -- to 1997s competing volcano movies.
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

According to Wiktionary, a volcano is "a mountain that contains a magma chamber attached to the mantle of the planet or moon and which periodically erupts forth, usually explosively, with lava and volcanic gases." There are many volcanoes, both active or dormant and extinct. .You will find very few entries in this book pertaining to specific volcanoes, although you can head to Wikipedia for any volcano you wish to know about.^ Many of you know what I am talking about (you call it the Not-So-Safeway), but for those of you who never cross the sacred boundary of your 98407 zip code, it's the Safeway...
  • Weekly Volcano - The alternative newsweekly for Tacoma and Olympia 3 February 2010 19:019 UTC www.weeklyvolcano.com [Source type: General]
  • Weekly Volcano - The alternative newsweekly for Tacoma and Olympia 3 February 2010 19:019 UTC www.weeklyvolcano.com [Source type: General]

^ Perhaps you want to know whether earthquakes or volcanoes are more powerful or destructive.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

^ Where you live will be determined by the information you find about earthquakes.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

Contents

Introduction

.This book covers volcanoes, how they erupt, where you can find them, and other interesting things about volcanoes.^ Things (and more) I Hate about Volcano .
  • Dante's Peak & Volano:  A Jabootu Nugget 28 January 2010 1:01 UTC www.jabootu.com [Source type: General]

^ He says his findings may mean that researchers need to re-assess their understanding of how submarine volcanoes are formed .

^ "This lesson is designed to help you understand what volcanoes are, their make-up, and how they are classified.
  • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

Ferdinandea14.jpg
VEIfigure.jpg

Contents

.
  1. Plate Tectonics
  2. Basics of Volcanoes
  3. Volcanic Eruptions
  4. The Volcanologist
  5. Special Topics
  6. Volcanism Note: this is the former book Volcanism.^ "In this lesson, students explore first-person accounts of volcanic eruptions throughout time and use the Internet to access second-hand information about volcanoes.
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    ^ Sections: Basics, Seismographs, Plate Tectonics, Faults, Waves, Seismograms, Inside the Earth, History and Earthquake Safety.
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    ^ A s of the 29th of January, the Kamchatkan Volcanic Eruption Response Team (KVERT) reported that activity of the volcano continues: a new viscous lava flow effuses at the lava dome.
    • News 3 February 2010 19:019 UTC www.intlvrc.org [Source type: FILTERED WITH BAYES]

    If you were redirected here, no worries. This is the book.

Wikiversity

This textbook is being used for the volcanology course at Wikiversity. If you have come over to read the textbook, then go right ahead.

Resources

  • Earthquakes-Volcanoes and earthquakes are commonly seen together. .You ought to check it out, for some ground to dig.
  • The USGS-The USGS studies, among other things, volcanoes and earthquakes.
  • e-explore.earth The DK E-guide to Earth.^ Information on earthquakes, volcanoes, and the Earths crust.
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    ^ Check out the Earthquakes page, too.
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    ^ Perhaps you want to know whether earthquakes or volcanoes are more powerful or destructive.
    • WEBSITES ON EARTHQUAKES & VOLCANOES 3 February 2010 19:019 UTC www.cumbavac.org [Source type: General]

    This is the section on volcanoes.

Citable sentences

Up to date as of December 10, 2010

Here are sentences from other pages on Volcano, which are similar to those in the above article.








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