What is the opening at the top of a volcano called?
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crater THANK YOU THE 2POINTS
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All fragments thrown into the air by a volcanic eruption are called pyroclastics. During a more violent eruption, the force of the blast sends superhot gas and millions of pieces of lava into the air. These particles are classified as bombs, cinders, or ash, depending on their size and shape. Small pieces of lava, which solidify almost immediately, form slivers of volcanic glass.\nTogether with rocks blown from the sides of a volcano, the entire collection of ejected material becomes a hot, fast-moving cloud of rock and ash. These flows can travel at great speed down the flanks of a volcano and into surrounding areas, causing extensive destruction. In 1902 the eruption of Mount Pelée, on the island of Martinique, created this type of pyroclastic blast and destroyed the town of Saint-Pierre, killing about 30,000 people.\n\nLike lava, pyroclastic material raining down on a volcano eventually compacts into solid layers that build up the volcano’s bulk. Some eruptions actually reduce the height of a volcano, because they are so powerful that they literally blow the top of the volcano off. In 1883 the cataclysmic explosion of Krakatau in Indonesia destroyed most of the island, which had been formed by the volcano.\n\n\nKrakatau 1883\nDestroyed entire island\nPumice Rafts (lava with lots of vesicles) trapped sailors for three days\nCaused Tsunami\nHeard as far as Australia
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Volcano is the result of Lava and gases gushing out of the surface of the earth at great heat and pressure.  The molten lava is running over the land and destroy the plants and trees and after cooling becomes rock there. Fresh lava  comes out and run in the available slope.  The result is a mountain is growing with fire and lava.  Thus the mountains are the result of volcano and lava.  When the pressure within the volcano is reduced the volcano takes rest.It will erupt at any time  and send lava and gases, fire in all the directions.  The centre of the earth is believed to contain very hot lava and gases which is likely to come out at any time in any part; and most likely in the soft surfaces .
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A blue flame with the bunsen air hole completely open is called a roaring flame. This flame shows a small purplish come inside the blue outer flame. The top of this cone is the hottest spot in the flame.\n\nsee pic \nhttp://www.blcleathertech.com/default.asp?id=99
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A volcano possesses explosive power plus a flow of volcanic lava that tends to follow i hope that helps. It combines both power and flow but a different kind to that of water.
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A stratovolcano is a tall, conical volcano composed of many layers of hardened lava, tephra, and volcanic ash. These volcanoes are characterized by a steep profile and periodic, explosive eruptions. The lava that flows from them is highly viscous, and cools and hardens before spreading very far. The source magma of this rock is classified as acidic, or high in silica to intermediate (rhyolite, dacite, or andesite. or basalt). This is in contrast to less viscous basic magma that forms shield volcanoes (such as Mauna Loa in Hawaii), which have a wide base and more gently sloping profile. Many stratovolcanoes exceed a height of 2500 m.\n\nStratovolcanoes are a by-product of the subduction of tectonic plates. The source melts of these volcanoes arise as a result of the dewatering of oceanic crust at specific pressure/temperature conditions as the plate subducts to lower depths. The water freed from the subducting slab allows partial melting of the overlying mantle rock, which rises due to its lower density relative to the surrounding mantle rock, and pools at the base of the crust. The melt is initially basic in composition. As it rises through the crust, it incorporates more acidic adjacent crustal rock, leading to a final intermediate composition. The water remains in the melt and upon eruption contributes to the explosive power of these volcanoes as superheated steam.\n\nAlthough stratovolcanoes are sometimes called composite volcanoes, volcanologists prefer to use the term stratovolcano to distinguish among volcanoes because all volcanoes of any size have a composite (layered) structure — that is, are built up from sequential outpourings of eruptive materials.
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When pressure from magma attempts to reach the surface, and is blocked by a "plug" of rock and other debris formed from earlier eruptions. The magma contains a lot of gas, so this, too, will add to the pressure on the plug, and eventually the pressure will become so great that it must be "relieved", hence causing an eruption (this is the more explosive type). A lesser type, involving lava eruptions, is when magma reaches the surface through breaks (faults, vents or fissures). There are other types of eruptions, like steam eruptions, or geysers (think of Yellowstone and Old Faithful), that can occur with any volcano. These mini eruptions are a result of water seeping into dormant fissures and making contact with magma below the surface. The water is instantly evaporated by the super-hot magma, and steam rises and shoots out from the open vent.
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Volcanoes are usually situated either at the boundaries between tectonic plates or over geology hotspots. Volcanoes may be either dormant (having no activity) or active (near constant expulsion and occasional eruptions), and change state unpredictably.\n\nSurprisingly, there is no 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 activity. Given the long lifespan of such volcanoes, they are very active. By our lifespans, however, they are not. Complicating the definition are volcanoes that become restless but do not actually erupt. Are these volcanoes active?
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Super Volcanoes are planet killers!!! Yellowstone is the first one that comes to my mind.\n\nHere's what wikipedia says:\n\n"A supervolcano refers to a volcano that produces the largest and most voluminous kinds of eruption on Earth. The actual explosivity of these eruptions varies, but the sheer volume of extruded magma is enough to radically alter the landscape and severely impact global climate for years, with a cataclysmic effect on life.\n\nThe term was originally coined by the producers of the BBC popular science program, Horizon, in 2000 to refer to these types of eruption. That investigation brought the subject more into the public eye, leading to further studies of the possible effects. At first, supervolcano was not a technical term used in volcanology, but more recently, in 2003 and 2004, the term has been used in articles. Though there is no well-defined minimum size for a "supervolcano", there are at least two types of volcanic eruption that have been identified as supervolcanoes: massive eruptions and large igneous provinces."
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They are small volcanos.
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http://en.wikipedia.org/wiki/Volcanos
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Greetings!\n\nWhat you are describing is known as a geyser
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http://www.geology.sdsu.edu/how_volcanoes_work/subducvolc_page.html\n\nstratovolcanoes\n\nbut on land your answer is probably going to be basaltic
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A dormant volcano no longer erupts regularly but has lava in the batholith and is capable of erupting.  An extinct volcano contains no magma and the batholith has hardened.  It cannot erupt.
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Depends on the composition of the magma.\n\nMagma high in silica tends to be thick & gas bubbles are trapped. The gas builds up & boom! Explosion.\n\nBasaltic lava tends to be "soupy" so that the gas bubbles escape. No explosions here.\n\n:)
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A subglacial volcano is a volcanic form produced by eruptions beneath a glacier or beneath the surface of a lake within a glacier. Today they are most common in Iceland and Antarctica; older formations of this type are found also in parts of Canada. Their shape tends to be characteristic and unusual, with flat top and steep sides. If the heat produced by the volcano is high enough to melt through the ice layer, however, the volcano assumes a more conventional shape.
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Careful: The questioner is correctly stating that magma is inside the earth's crust (or lithosphere).  Lava is magma that has erupted.  Magma rises up from within the lithosphere because it is more bouyant (wants to float) that the dense rock around it.  Lava is different, once it's on the surface, it does tend to flow with gravity, like water.