Just like baking cookies, metamorphic rocks need to be "cooked" just right!
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How Much Do Metamorphic Rocks Change?

Sometimes rocks are metamorphosed just a little bit.

Sometimes rocks are changed a lot.

It depends on how much the rocks are affected by heat and pressure.

Rocks that are metamorphosed just a little bit, form within the Earth at temperatures a little hotter than the oven temperature needed to bake chocolate chip cookies. Metamorphic rocks are greatly changed when they form in conditions about four times hotter than the baking oven. At that temperature, the rocks almost melt!


Last modified June 20, 2003 by Lisa Gardiner.

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