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Volcanoes Animation of a volcano
Cinder ConeCinder Volcanoes are the simplest type of volcano. They are built from particles and blobs of congealed lava ejected from a single vent. Lava is blown into the air, which breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone. Most cinder cones have a bowl-shaped crater at the summit, and rarely rise more than a thousand feet or so above their surroundings.
Composite/StratovolcanoTypically, composite volcanoes are steep-sided, symmetrical cones of large dimension built of alternating layers of lava flow, volcanic ash and cinders. Composite volcanoes will rise as much as 8,000 feet above their base. Most composite volcanoes have a crater at the summit, which contains a central vent or a clustered group of vents. One essential feature about composite volcanoes is the conduit system. This is when the magma (molten rock material) from a reservoir deep in the Earth's crust rises to the surface. This type of volcano is built by the accumulation of materials erupted through the conduit, which increases in size as lava, cinders, and ash are added to its slopes.
Shield VolcanoShield volcanoes are built almost entirely of fluid lava flow. Flow after flow pours out in all directions from a central summit vent, which builds a broad, gently sloping cone - much like a warrior's shield or a plateau. Shield volcanoes can be easily identified because they are tall and broad, with flat, rounded shapes.
Olympus Mons Location: Mars Type: Shield volcano Facts: • Olympus Mons a Latin term meaning "Mount Olympus" is the tallest known volcano and mountain in our solar system • Roughly the size of the American state of Arizona and three times taller than Mt. Everest; about 20x wider than it is tall. • The extraordinary size of Olympus Mons is likely due to the fact that Mars does not have tectonic plates. Thus, the crust remained fixed over a hot spot and the volcano continued to discharge lava, bringing it to such a height. Formed the same way as the Hawaiian Islands. Last Eruption: as recently as 40 mya; may still be an active volcano??
Mt. Pinatubo Location: Philippines Type: Composite volcano/stratovolcano Facts: • Has had between 6 and 12 eruption cycles • Largest eruption was 35,000 years ago • Most of the volcano was blasted away in the 1991 eruption • Surrounded by smaller volcanoes that are actually vents to the larger volcano Last Eruption: 1991-1992, although it is still an active volcano
Mount Hood Location: Oregon, USA Type: Composite volcano/stratovolcano Facts: • Tallest mountain in Oregon; the base is over 92 miles wide • Has had 4 active eruption periods in the last 15,000 years • Formed 500,000 years ago • Very popular with skiers, hikers and climbers; many communities would be threatened by a modern day eruption of this volcano Last Eruption: 1790's, not long before Lewis and Clark's expedition to the Pacific Northwest
Kilauea Location: Hawaii, USA Type: Shield volcano Facts: • Youngest volcano in Hawaii • One of the most active volcanoes on Earth; over 90% of the surface is covered in lava • Formed by a hotspot under the Pacific plate • Most of the volcano is below sea level • Has a large caldera Last Eruption: November 2009
Paricutin Location: Mexico Type: Cinder Cone volcano Facts: • Grew in a cornfield in an eruption that began in 1943; largest period of growth was the first year, continued to grow for 8 years • Lava flow covered 10 square miles • It’s unique growth cycle allowed scientists to study volcanoes more closely Last Eruption:1952
Mount Cotopaxi Location: Ecuador Type: Composite volcano/stratovolcano Facts: • Located in the Ring of Fire • Means “throne of moon” • Has erupted 50 times since 1783 • Tallest volcano in Ecuador • It’s eruptions produced mudflows that traveled over 60 miles Last Eruption: 1904-has been dormant for the last 35 years
Mount Saint Helens Location: Washington, USA Type: Composite/stratovolcano Facts: • Massive eruption in May, 1980 sent thousands of tons of ash into atmosphere and covered 150 square miles; the top of the volcano was destroyed in minutes; vegetation has yet to recover Last Eruption: 2008
Mount Rainer Location: Washington, USA Type: Composite/stratovolcano Facts: • Formed 730,000 years ago • Steepest volcano in Cascade range • Over the last 100,000 years the erosion has been greater than the growth; due to glaciers • Has a high number of avalanches; covered in large amounts of ice and snow Last Eruption: 1894
Mauna Loa Location: Hawaii, USA Type: Shield volcano Facts: • Largest volcano on Earth; one of the most active • Began to form nearly 1 million years ago • Makes up ½ the area of the island of Hawaii • There is a caldera located at the summit • Has erupted 15 x since 1900 Last Eruption: 1984
Mount Fuji Location: Japan Type: Composite/stratovolcano Facts: • One of the most well-known volcanoes • Japan’s largest volcano/highest mountain; actually made up of 3 volcanoes • Currently dormant • Eruptions have resulted in 0 fatalities • Has a large crater from the 1707 eruption • Has erupted 16 times since 781 AD Last Eruption: 1707
Mount Shasta Location: California, USA Type: Composite/Stratovolcano Facts: • Second highest mountain in the Cascades • Erupts approximately every 800 years • Comprised of 4 overlapping eruption centers Last Eruption: 1786
Mt. Etna Location: Italy Type: Composite volcano/stratovolcano Facts: • One of the world’s most studied volcanoes • Second largest active volcano in Europe • One of the world’s largest continental volcanoes • Surface is covered by historic lava flows Last Eruption: 2008