Volcanism

The definition of a volcano has gradually progressed throughout these many years. As of today, volcanoes are known as mountains making up the earth’s surface, forming magma which comes up from the crust or mantle. When there is high pressure coming from the gas bubbles within the magma chamber, it will build up enough to break through the crust and reach the top. This will then erupt, creating lava. Volcanologists can look for signs when a volcano is about to erupt, but the exact science cannot be proven and is left unknown.^[1]

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Volcanism, vulcanism, volcanicity, or volcanic activity is the phenomenon where solids, liquids, gases, and their mixtures erupt to the surface of a solid-surface astronomical body such as a planet or a moon.^[2] It is caused by the presence of a heat source, usually internally generated, inside the body; the heat is generated by various processes, such as radioactive decay or tidal heating. This heat partially melts solid material in the body or turns material into gas. The mobilized material rises through the body's interior and may break through the solid surface.^[3][4]