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Rock Types and the Rock Cycle: Igneous Sedimentary Metamorphic

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Did you know that every rock you pick up has changed many times throughout it's history? It's true - rocks change. Geologists like to describe the changes via a rock cycle. They also classify rocks into one of three types: igneous, sedimentary and metamorphic.

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A quick introduction to igenous rocks. Download the flow chart at http://www.hmxearthscience.com/Sammartano/Rocks%20Flow%20Chart.pdf

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A brief introduction to metamorphic rocks. You can download a copy of the flowchart at http://goo.gl/3PRQb

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A brief introduction to sedimentary rocks. You can download a copy of the flowchart at http://goo.gl/3PRQb.

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Keep in mind that the example on the previous page didn't show all the ways rocks move through the rock cycle. For instance, igneous rocks can become metamorphic rocks without reaching Earth's surface or becoming sedimentary rocks. Another variation from the example is that any type of rock can become a new rock of the same type.

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Classzone.com has been retired and is no longer accessible. Because of the age of this application, the programs supported by this platform are not able to benefit from the technological improvements in accessibility, security, and HMTL5 (non-Flash) that we have incorporated into our newer programs and platforms in recent years.

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Created by Oxford University Museum of Natural History, this site teaches you all about the natural world.