Rocks Really Rock!

Igneous, Metamorphic, and Sedimentary
By:Rhea Karumuru

There are three types of amazing rocks called Igneous, Metamorphic and Sedimentary. I will tell you about them. The cool thing about rocks is that one rock can turn into an another. Like a cycle called "The Rock Cycle." First let me explain the kinds of rocks there are and the videos will explain the cycle.

Sedimentary

Sedimentary rocks are formed when water and wind break down parts of rocks and seashells.  Over time, layers of the broken parts get squeezed and cemented together with no heat.  Sedimentary rocks are really soft and they can break easily. This is the only kind of rock which you can see fossils. Some examples of  Sedimentary rocks are 1.limestone          2.sandstone          3.coal          4. salt

Metamorphic

Metamorphic rocks are formed underneath the surface of the earth from the cane that occurs due to heat and pressure. These kinds of rocks will have ribbon like layers and crystals that form from minerals growing over time on their surface. Some examples of Metamorphic rocks are       1. marble 2.slate

Igneous

Igneous rocks are formed by cooled magma. Magma is a hot orange liquid that comes from inside the Earth. Sometimes it cools on the surface of the Earth form volcanoes.(then its lava) Other times it will cool in side the Earth. Igneous rocks are smooth and glass like. Since air bubbles get trapped in side the rock during the cooling process, there is small holes in the rock, like Swiss cheese. Some examples of Igneous rocks are  

1. basalt                 2. obsidian

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