VOLCANOES

A volcano is a conduit which connects directly the top of the solid crust with lower levels of it. It is also a geological structure by which emerging magma (molten rock) in the form of lava and gases inside the planet. The rise usually occurs in episodes of violent activity called "rash", which can vary the intencidad, duration and frequency channels being from lava flows to extremely destructive explosions.

Generally acquire a characteristic conical shape is formed by underground magma pressure and the accumulation of material from previous eruptions. On top of the volcano can find its crater or caldera.Volcanoes can be found in the earth and other planets and satellites, some of which are made of materials that we consider "cold", are they cryovolcanism. That is, they act as ice cold rock as the internal liquid water acts as the magma, that happens, for example, in the cold moon of Jupiter named Europa.

In general, volcanoes form at tectonic plate boundaries, although there are exceptions called hot spots or hot spots located in the interior of tectonic plates, such as the Hawaiian Islands. There are also underwater volcanoes that could eject enough material to form volcanic islands.

The Earth is not the only planet in the Solar System that has volcanic activity. Venus has an intense volcanism volcanoes about 500,000. Mars has the highest peak of the solar system: Olympus Mons, a volcano off given by a base of about 600 km and over 27 km in height. However, this planet seems to have no significant volcanic activity.Our moon is covered with vast fields of basalt, suggesting that had a short but significant volcanic activity today is probably extinct.Due to the low temperatures of space, some volcanoes in our solar system are composed of ice that acts as a rock, while its internal liquid water acts as the magma, that happens, for example, in the cold moon of Jupiter named Europa. These are called criovolcáns.

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