Volcanic Processes
Magma from the mantle or lower crust rises through its crust to the surface. If magma reaches the surface, its behavior depends on the viscosity of the molten constituent rock. Viscous (thick) magma produces volcanoes characterised by explosive eruptions, while non-viscous (runny) magma produce volcanoes characterised by an effusive eruptions pouring large amounts of lava onto the surface.
In some cases, rising magma can cool and solidify without reaching the surface. Instead, the cooled and solidified igneous mass crystallises within the crust to form an igneous intrusion.
Read more about this topic: Volcanism
Famous quotes containing the words volcanic and/or processes:
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—Stefan Zweig (18811942)
“The higher processes are all processes of simplification. The novelist must learn to write, and then he must unlearn it; just as the modern painter learns to draw, and then learns when utterly to disregard his accomplishment, when to subordinate it to a higher and truer effect.”
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