SME
Grade 12 Science · Earth & Space Science
Volcanoes, crustal deformation and mountain building
Compare shield volcanoes, composite volcanoes and cinder cones, and see how the lava builds each shape.
Explore
Runny basalt flows spread thin before they cool, building gentle slopes.
Eruptions are mostly quiet lava flows, as on Hawaii.
Assumptions
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Silica makes magma sticky; sticky magma traps gas.
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Trapped gas makes eruptions explosive.
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See what you know: 5 questions on this topic
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