what is the anatomy of a volcano?
465931
Ash  | Lava flow | Lava dome | Lava | Vent | Tephra | Caldera | Lahar | Fissure | Dike | Magma
821602
The first site below has a good simple explanation of earthquakes and volcanoes.  The second site focuses on recent earthquakes and volcanoes around the world.\nMy favorite video on Volcanoes is from the Eyewitness video series... great photography  and fast moving.  You might be able to find it in a video rental store or the library.  I'm not sure what you needed to know about this subject, so here is a variety.  Hope one of them helps.
651917
A volcano is a geological landform usually generated by the eruption through a planet's surface of magma, molten rock welling up from the planet's interior. Other forms of volcano include ice volcanoes (particularly on some moons of Jupiter, Saturn and Neptune) and mud volcanoes. On Earth, volcanoes tend to occur near the boundaries of crustal plates. There are Diff types of volcanoes:\n1)Extinct--lowest possible chance of erupting.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.\n\n2)Dormant --those that are not currently active but could become restless or erupt again. Confusion however, can arise because many volcanoes which scientists consider to be active are referred to as dormant by laypersons or in the media.\n3)Active--it is currently erupting or showing signs of unrest, such as unusual earthquake activity or significant new gas emissions. Many scientists also consider a volcano active if it has erupted in historic time.\n  \nIt is important to note that the span of recorded history differs from region to region; in the Mediterranean, recorded history reaches back more than 3,000 years but in the Pacific Northwest of the United States, it reaches back less than 300 years, and in Hawaii, little more than 200 years. The Smithsonian Global Volcanism Program's definition of 'active' is having erupted within the last 10,000 years.So A volcano may occur anytime as earthquakes do.
158817
Several ways. This also depends on the type of eruption. Often earthquakes occur before, or during an eruption causing things to topple. Also, often the size of the volcano itself changes. Lava cools to rock after flowing over the landscape, and kills the organic material it comes into contact with. The gas released during an eruption is also deadly! If it is an eruption like Mt. St. Helens was, the land is covered in ash and decimated by mudslides.
54493
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?
760131
4. D\nThe most explosive volcanoes are those containing a lot of silica.  The shape of the silca molecule is a bit like a pyramid which means that cannot move past each other very easily.  This makes them very viscous and so it takes much more energy to get it to move and the energy comes out in a single event.\n\n12. B\nIt's the difference between min and max.
917724
Because of the volcanoes.
1095020
Cinder cones are the simplest type of volcano. They are built from particles and blobs of congealed lava ejected from a single vent. As the gas-charged lava is blown violently into the air, it 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. Cinder cones are numerous in western North America as well as throughout other volcanic terrains of the world.
676415
Go here:\n\nhttp://www.fema.gov/kids/volcano.htm
924357
volcanoes are built when tectonic plates push together, the way mountains are formed. except volcanoes have magma inside of them. the gas and magma inside are under extreme pressure, and this pressure pushes its way through small cracks in the rock, eventually escaping in an eruption of gas that brings lava with it. a lot of people have been killed by eruptions, but i cant tell you how many. the lava takes weeks or months to cool down unless it hit the water, which will cool it in a matter of days.
819369
The primordial soup of early volcanoes.
425045
The answer is: D. Volcanoes that have large amounts of silica\n\nHere is the reason why it is D:\n\nMagma that contains high amounts of silica is very viscous. That means it is very thick. Because of its thickness, gases can not escape & will build up behind the magma. When the pressure builds up enough, an explosion occurs. Large chunks of lava rock are thrown from the volcano in all directions. The debris fallout from these types of eruptions is extremely dangerous!\n\nIn 1980, Mt. St. Helens was an explosive composite volcano. Half the mountain was gone in a matter of minutes. The problem with that particular volcano was not the falling rock debris (few people). In fact w/ St. Helens, it was the ash which is small particles of volcanic glass (a.k.a. silica). These minute particles of glass can cut your lungs. Also, people living & camping down below the mountain were caught up in mudflows caused by the melted snowcaps. Also, pyroclastic flows can race down the mountainside at tremendous speeds. Anyone caught in the way would be annihilated.\n\nSea water can cause explosive steam eruptions but this occurs in submarine volcanoes (underwater). No one is around to be in its way.\n\n:)
91291
The short answer is plate tectonics. Volcanoes can be divided into three major groups, those that are connected to a spreading center, like the mid-ocean ridges, those connected to a subduction zone, like Mt.St. Helens, or much of the Indonesian archipelago, and intraplate volcanism like Yellowstone. \n\nWhere the lithosphere (or crust) overlies an area within the asthenosphere (the layer of the earth under the crust) there are currents rising that cause volcanoes to form. These areas are called spreading centers. At the edges of the oceanic plates the plates often are forced under continental or even other oceanic plates. Where these plates are being forced downward, called subduction, there are volcanoes formed by melting magma rising from the descending plate. Most of the volcanoes around the edges of the Pacific Ocean are of this type, and are the reason it is called the "ring of fire".\n\nThe other group of volcanoes are related to what are called hot spots. These are places under the crust where the asthenosphere is especially hot. Yellowstone, and the Hawaiian Islands are examples of this. The hot spot under Hawaii is stationary, and as the Pacific plate has moved across it, it has produced a long chain of volcanic islands. \n\nYou can explore what makes volcanoes work at the following website sponsored by NASA:\nhttp://www.geology.sdsu.edu/how_volcanoes_work/Home.html
598947
1st answerer is good on location.  Difference between the types are due to the composition of the lava and where they occur.\n\nShield volcanoes, such as those found in Hawaii, have magma that is very low in silica, high in basalt (often referred to as "basaltic" volcanoes).  This means that the lava flows easily, instead of exploding.  That is why there is not a steep slope to the volcano and the biggest threat is just to remain out of the lavas way.\n\nStrato-volcanoes (Mt. St Helens) are found in subduction zones and produce a lava that is described as Andesitic (named after the Andes Mountains in South America).  This lava is high in Silica, which makes it much more viscous, and therefore, more explosive.  This explosiviness defines the shape of the cone, with much steeper sides.  With these types of volcanoes you have the explosive lava threat, but you are also threatened by pyro-clastic flows, and lahars.\n\nCinder cones are the same, compositionally as strato-volcanoes, but are not always located in a subduction zone, and are usually quite alot smaller.
871525
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.
834976
My guess is dissipation, hydrothermal, volcanic. Just guessing.
998878
Both are held under pressure. The molten rock (lava) is full of gases like a fizzy drink and when the pressure is released the gases escape causing an explosive reaction.  IE. the volcano erupts and the drink fizzes up when the gas is released at normal atmospheric pressure.