Portal:Volcanoes
The Volcanoes Portal A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot, molten rock, ash, and gases to escape from below the surface. Violent explosive eruptions from such vents often produce craters or calderas and coat extensive areas in volcanic ash, while the lava from comparatively gentle effusive eruptions may eventually form large plains, cones or mountains. Volcanoes are generally found where tectonic plates are pulled apart or come together. A mid-oceanic ridge, such as the Mid-Atlantic Ridge, hosts volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire contains many volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are not commonly created at transform boundaries, where two tectonic plates slide past one another. Volcanoes can be caused by mantle plumes. The resulting 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. Intraplate volcanoes can also form where there is stretching and thinning of the Earth's crust, as in the Wells Gray-Clearwater volcanic field and the Rio Grande Rift in North America and the European Rhine Graben with its Eifel volcanoes. Selected article Selected biographyHowel Williams (1898-1980) was a noted American geologist and volcanologist. He was born of Welsh parents in Liverpool, England, on October 12, 1898. He received a BA in geography in 1923 and an MA in archaeology in 1924 from Liverpool University. He studied geology at the Imperial College of Science and Technology in London. In 1926 he moved to the University of California at Berkeley in 1926. In 1928 he was awarded the degree of D.Sc. from the University of Liverpool and published his first papers on the geology of various California volcanic regions. He published many studies on the volcanoes of California, but is most noted for his "The Geology of Crater Lake National Park" in which he recognized the nature of the collapse of the crater and extended the work to develop the principles of volcanic caldera formation. He did extensive early work on the geology of Central America (often sketch-mapping from the windows of second-class buses), and of the Galapagos Islands. In Latin America, Williams put to good use his early background in archeology. For instance, he used petrographic techniques to trace the origin of stone used in the giant Olmec sculptures of La Venta, Tabasco Mexico. Did you know
Volcanoes news
Volcanoes topics Core topics: Volcano • Volcanology • Igneous petrology • Lava • Magma • Decade Volcanoes • List of volcanoes • Plate tectonics • Hotspot Types of volcanoes: Fissure vent • Shield volcano • Lava dome • Cinder cone • Stratovolcano • Supervolcano • Submarine volcano • Subglacial volcano • Mud volcano Types of eruptions: (Overview) • Strombolian • Vulcanian • Peléan • Hawaiian • Surtseyan • Plinian • Submarine • Subglacial • Phreatic Related portalsSelected picture
False-color mosaic of the moon, constructed from a series of 53 images taken by Galileo spacecraft. Volcanic rock is shown as blue to orange shades. Selected quote
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The project collaboration is a drive to improve our coverage of an important volcano-related topic. Once the article has been improved significantly, a new collaboration is chosen. Please improve the article any way you can. WikiProjectsCategories
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Featured work and other approved content Featured articles: 1980 eruption of Mount St. Helens • 2007–2008 Nazko earthquakes • Amchitka • Armero tragedy • Craters of the Moon National Monument and Preserve • Cerro Azul (Chile volcano) • David A. Johnston • Enceladus (moon) • Geology of the Lassen volcanic area • Io (moon) • Loihi Seamount • Mauna Kea • Mauna Loa • Metacomet Ridge • Mono-Inyo Craters • Mount Cayley volcanic field • Mount St. Helens • Mount Tambora • Nevado del Ruiz • Surtsey • The Volcano (British Columbia) • Triton (moon) • Upper and Lower Table Rock • Volcanism on Io • Volcano (South Park) • Yellowstone National Park Featured lists: List of volcanoes in Indonesia • List of volcanoes in the Hawaiian – Emperor seamount chain • List of largest volcanic eruptions Featured pictures: There are currently 42 volcano-related Featured pictures. A full gallery can be seen here.  Good articles: Abyssal plain • Amak Volcano • Anahim hotspot • Axial Seamount • Ben Nevis • Bowie Seamount • Crater Lake • Davidson Seamount • Ferdinandea • Gareloi Volcano • Geyser • Glacier Peak • Hawaii hotspot • Hualālai • Kohala (mountain) • Lake Toba • Minoan eruption • Mount Adams (Washington) • Mount Bailey • Mount Baker • Mount Cleveland (Alaska) • Mount Edziza volcanic complex • Mount Garibaldi • Mount Hood • Mount Kenya • Mount Rainier • Mount Redoubt • Mount Tehama • Mount Thielsen • Mount Vesuvius • Peter I Island • Roxy Ann Peak • Rùm • Sakurajima • Silverthrone Caldera • Staffa • Types of volcanic eruptions • Volcanic ash • Weh Island • Wells Gray-Clearwater volcanic field • Yamsay Mountain Valued pictures: A gallery of volcano-related valued pictures can be seen here. Associated Wikimedia
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