If lava will melt through anything in this entire world, how come when a volcano erupts, the lava doesn't just melt through the ground and just return to the magma beneath the earth's surface?

Cory

Dear Cory,

In general, magma gets to the surface by forcefully moving rocks out of the way. That is why earthquakes precede eruptions. Gas pressure in the magma cracks the overlying rocks. The magma moves into the new crack. The process repeats until the magma reaches the surface. If the magma loses too much heat along the way it solidifies and stops on the crust (no eruption/volcano). Some batches of magma do melt surrounding rocks but this is usually a minor process.

Steve Mattox, University of North Dakota

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