Transcription: Volcanoes are holes or vents in the Earth's crust created when molten material or magma under the crust is forced upward through the surface. Magma collects in a chamber beneath the crust. Pressure increases, forcing it up through cracks and fissures and a conduit to the surface is created. Hot gases try to escape but are trapped in the magma. The surface begins to bulge. Finally, pressure can no longer be contained. Gases and fragments of Earth are released in a violent explosion. A volcano may erupt many times during its lifetime of thousands of years. Material expelled during the eruptions ...
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