How are volcanoes formed?

Answer

Volcanoes are formed through the movement of magma and tectonic plates. Magma either pushes up through the middle of a lithosphere plate or around the boundaries of two plates, forming a volcano.

When magma is produced around plate boundaries, it is called interplate volcanic activity. This activity is caused by unusually hot mantle material forming in the lower mantle and pushing up into the upper mantle. The mantle material then forms a plume shape and wells up to create a hot spot under a specific part of the Earth's surface. Due to the unusual amount of heat within the mantle material, it melts and forms magma that is just under the Earth's crust.

The hot spot, where the magma spews forth, remains stationary, but as the continental plates move over the spot, the magma will begin creating strings of volcanoes. These volcanoes will eventually die out once they move past a particular hot spot.

Most volcanoes are created through subduction zone volcanism or hot spot volcanism. The structure of a volcano depends on a number of factors, primarily the composition of the magma. Additionally, unlike land volcanoes, the magma produced at ocean ridges just hardens to form new material for the Earth's crust.

Q&A Related to "How are volcanoes formed?"
Volcanoes form when magma from deep inside the Earth leaks up into the crust and forms a pool. It will eventually erupt causing lava to spill out. It is a lot of pressure that is
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They are formed when an oceanic plate goes under another oceanic plate. Causing it to go under to the mantle. Which causes it to burn making the magma turn into lava. Once the lava
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a stratus volcano forms starting from a mountain that takes magma from around the center of the earth and blow off the top of the mountain and sometimes forms land.
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1 Additional Answer
Ask.com Answer for: how are volcanoes formed
Volcanoes are created from a opening in the Earth's crust, which allows hot magma, ash and gases to escape. They form in the shape of cones, domes or simple fissures.
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A volcano is a vent through which molten rock known as magma rises from underground to the Earth's surface. Volcanoes are formed when magma from within the earth's ...
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