Magma is molten rock that is deep underground.
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Courtesy of Boise National Forest


Pretend that you are an explorer traveling to the center of the Earth. You would find that the deeper you travel, the hotter it gets! Beneath the crust, in the mantle layer, it is hot enough that rock can melt. When rock melts and turns into a liquid, we call it "molten". The molten rock is called magma. Magma is so hot that it glows bright white. You would need sunglasses to look at it!

If magma flows into an area underground that is less hot, it cools, becomes yellow, and then red. As it cools slowly, minerals form crystals making a plutonic rock like granite.

If magma finds a crack in the Earth and comes to the surface, it is called lava!

Last modified June 17, 2003 by Lisa Gardiner.

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