Volcanos
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Volcanos are areas of the Earth's surface through which magma and volcanic gases pass. There are two types of volcanic eruptions: nonexplosive and explosive. An explosive eruption is very rare, but it is extremely destructive. During an explosive eruption, clouds of hot debris, ash, and gas rapidly shoot out from the volcano. Nonexplosive are most common and produce relatively calm flows of lava. A magma chamber a body of molten rock deep underground that feeds a volcano. Magma rises from the magma chamber through the cracks in the Earth's crust to openings called vents. Magma is released through the vents during an eruption. There are three types of volcanoes: cinder cone, composite, and shield. Most volcanic eruptions occur in the Ring of Fire. (my.hrw.com)