Q:

Why are there volcanoes?

A:

Quick Answer

Volcanic vents allow the Earth to release built up gases from the heat and pressure emanating from its core. Magma rises towards the surface, and as the pressure builds the magma seeks outlets through which to flow. The higher the pressure build-up, the greater the volcanic explosion.

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Why are there volcanoes?
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Full Answer

Volcanoes in areas with more porous soil allow for the steady release of magma and are less likely to have severe explosions. Magma comes from rocks melted by the heat of the Earth's core. Because it is less dense than the un-melted rock, it slowly pushes up towards the surface. The continual creation of magma requires volcanoes for release both on Earth and other planets.

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Related Questions

  • Q:

    What are some facts about underwater volcanoes?

    A:

    One interesting fact about underwater volcanoes is that they deposit about 75 percent of the annual magma output on Earth. The molten magma and hardened lava shape the ocean floor and create the edges of the new plates on the ocean floor.

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  • Q:

    Are all volcanoes the same?

    A:

    No two volcanoes are exactly the same, as they all have differences in dimensions of their mountains and craters, as well as their relative frequency and type of eruption. Volcanoes come in cinder cone, shield and stratovolcano varieties.

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  • Q:

    How do volcanoes erupt?

    A:

    Volcanic eruptions can either be effusive or explosive. An effusive volcanic eruption occurs when the lava pours out onto the ground from the volcano's vent. When the molten rock or magma is thin and runny, gases can easily escape and the lava flows freely and travels far. An explosive volcanic eruption is caused by thick and sticky magma, which prevents gases from escaping and causes them to explode violently.

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  • Q:

    What impact do volcanoes have?

    A:

    The primary impact volcanoes have on the environment is the release of volcanic gases into the atmosphere. Volcanoes release around 130 million tons of carbon dioxide each year, as well as toxic pollutants like sulfur dioxide, hydrogen sulfide, hydrogen chloride and hydrogen fluoride. However, volcanoes can also have a positive impact on the environment because the lava and ash produced by an eruption contain valuable nutrients for the soil.

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