1. Rocks

2. Categories
Igneous Sedimentary Metamorphic Petrifaction

3. How do you think rocks form?

4. Sedimentary Rocks
Formed when layers of sediment are pressed together. Pressure and heat cement the layers into solid rocks.

6. Igneous Rocks
Formed when molten or liquid matter from inside Earth comes to the surface, cools, and hardens.

7. Metamorphic Rocks
Formed when heat and pressure over long periods of time work to fuse together other kinds of rock.

9. Petrified Rock
Rock formed when plant or animal remains are replaced with minerals and chemicals.