What Is a Volcano?
A Volcano is a mountain or hill, typically conical, having a crater or vent through which lava, rock fragments, hot vapour, and gas are or have been erupted from the earth's crust. They are formed when magma from within the Earth's upper mantle works its way to the surface. At the surface, it erupts to form lava flows and ash deposits. Over time as the volcano continues to erupt, it will get bigger and bigger.
How volcanoes Form Video:
Types of volcanoes
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Shield Volcano: “A broad domed volcano with gently sloping sides, characteristic of the eruption of fluid, basaltic lava.” (dictionary.com). An example of a shield volcano is Hawaii’s Kīlauea volcano. Stratovolcanoes (A.K.A Composite Volcanoes): “A large, steep volcano built up of alternating layers of lava and ash or cinders.”(dictionary.com). An Example of a Stratovolcanoes is Mount Helen. Cinder Cones: A steep, conical hill consisting of glassy volcanic fragments that accumulate around and downwind from a volcanic vent. Cinder cones range in size from tens to hundreds of meters tall. (dictionary.com). An example of a Cinder Cone volcano is, Mt. Rukinear in the Democratic Republic of the Congo. |
What Causes Volcanoes To Erupt?
Volcanoes are the earths way to cool off and release internal heat and pressure.
The cause of volcanic eruption is because of a build up of pressure and density below the volcano in the magma chamber or a build up of pressure from beneath the earth. Eventually, when the pressure below is too intense, a volcano explodes. Volcanoes are most common in areas of “seismic activity”, which is where the earths continental plate pull apart or collied. An example of a “seismic area” is the “ring of fire”. These types of volcanoes are know as “Boundary” volcanoes. When tectonic plates move, that causes an earthquake. So when tectonic plates, that are found in a near proximity to a volcano, moves it will cause a volcano to erupt. Volcanoes can also be found away from the plate lines, know as “Hot Spot” volcanoes. A hot spot is where the earth crust melts. Hawaii’s volcanoes are perfect examples of hot spot volcanoes.
The cause of volcanic eruption is because of a build up of pressure and density below the volcano in the magma chamber or a build up of pressure from beneath the earth. Eventually, when the pressure below is too intense, a volcano explodes. Volcanoes are most common in areas of “seismic activity”, which is where the earths continental plate pull apart or collied. An example of a “seismic area” is the “ring of fire”. These types of volcanoes are know as “Boundary” volcanoes. When tectonic plates move, that causes an earthquake. So when tectonic plates, that are found in a near proximity to a volcano, moves it will cause a volcano to erupt. Volcanoes can also be found away from the plate lines, know as “Hot Spot” volcanoes. A hot spot is where the earth crust melts. Hawaii’s volcanoes are perfect examples of hot spot volcanoes.
Process To an Eruption
The process of a Volcanic eruption begins when the magma chamber that is located below the Earths surface builds up with pressure. This then causes the magma to be force up towards the top of volcano. As it reaches closer to the surface, it is pushed through vents which leads to the eruption of the volcano. When the magma reaches the earths surface, it is called lava. Depending on the type of volcano, the lava will either gently flow or rapidly erupted into the air. During a volcanic eruption, not only does lava flow out, but rocks that have been pulled loose or torn by gases will also be blown out along with the lava. The process of a volcanic eruption is similar to shaking a bottle of soda. The pressure builds up inside and when released, it shoots out.