what are characteristics of volcanoes?
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They tend to have very steep slopes and are symmetrical. They sometimes rise up to 10,000 feet above sea level and create some of the planet's most majestic mountains. The eruptions from this type of volcano can often be very violent, throwing rock, ash and lava high into the air.
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In general, the more felsic the magma the greater the volatile content. So mafic/basaltic volcanoes are fairly quiescent, intermediate/andesitic volcanic eruptions are moderately explosive, and felsic/rhyolitic volcanoes may be extremely explosive.
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Volcanoes and ridges are landforms that are created by the movement of tectonic plates. Some volcanoes are formed when the plates pull apart under the ocean. ... Other volcanoes are created when a tectonic plate slides under another. As the bottom plate is heated up by the Earth's hot mantle, a material called magma forms.
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Real volcanoes in nature commonly fit within three basic types. Shield volcanoes, considered the least dangerous type, have low, rounded appearances caused by hot, fluid lava formation. Shield volcanoes produce mostly lava and only a little ash and coarse material. Composite cone volcanoes present a very real danger.
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Volcanoes are present throughout the terrestrial planets. Venus, Earth, and Mars have active ones, while Mercury's volcanoes are no longer active. ... Earth has multiple volcanoes, whereas Mars only has two very large ones. The inner planets have volcanoes because they contain hot magma.
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['Covers 20% of the Earth Surface. ... ', 'Several Continents by its sides/ Unique Location. ... ', 'The Highest Point is at the Sea Level Itself. ... ', 'Limited Marine Life. ... ', 'Has Unique Chemical and Physical Properties. ... ', 'Has Several Tectonic Plate Boundaries. ... ', 'Has Lowest Oxygen Content. ... ', '6000km of River Run.']
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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.
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There are two main types of volcano - composite and shield. The two types of volcano form in different places and have very different characteristics.
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Volcanoes have a serious of hazards (e.g. lava flows, ash fall, pyroclastic flows, climate changes on a global scale) that relate into different dangers or risks. The risks when visiting an active volcano depend on which risk zones of the volcano are visited and for how long.
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['It is fine textured and clayey in nature.', 'It has high amounts of lime, iron, magnesium and generally low quantities of phosphorus, nitrogen and organic matter.', 'It is black in colour since it is formed from weathered lava rocks.']
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Volcanic eruptions vary widely in strength. On the one extreme there are effusive Hawaiian eruptions, which are characterized by lava fountains and fluid lava flows, which are typically not very dangerous. On the other extreme, Plinian eruptions are large, violent, and highly dangerous explosive events.
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Definition: A volcanic eruption occurs when magma is released from a volcano. Volcanic eruptions can be quite calm and effusive, or they can be explosive. Effusive eruptions produce lava flows, while explosive eruptions produce ash and pyroclastic density currents. Volcanic Eruption.
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A volcano is formed when hot molten rock, ash and gases escape from an opening in the Earth's surface. The molten rock and ash solidify as they cool, forming the distinctive volcano shape shown here. As a volcano erupts, it spills lava that flows downslope. Hot ash and gases are thrown into the air.
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The primary factors that determine whether a volcano erupts violently or quietly include magma composition, magma tempera- ture, and the amount of dissolved gases in the magma.
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When magma erupts at the surface it can form different types of volcanoes depending on the viscosity, or stickiness, of the magma, the amount of gas in the magma, and the way in which the magma reached the surface. Different types of volcanoes include stratovolcanoes, shield, fissure vents, spatter cones and calderas.
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Composite Volcano. Geologists have identified 3 major types of volcanoes. There's the shield volcano, formed from low viscosity lava that can flow long distances. There are cinder cone volcanoes, which are made by the eruption of lava, ash and rocks that build up around a volcanic vent.
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Volcanoes happen when magma rises to the surface of the earth, which causes bubbles of gas to appear in it. This gas can cause pressure to build up in the mountain, and it eventually explodes. When the magma bursts out of the earth, it is called lava.