1. Metamorphic Rocks Rock transformations in the planet

2. What are they? Metamorphic rocks are transformed by heat & pressure in the earth. Magma can contact the rock to transform it. Regions of plate tectonics cause high levels of heat due to the movement of the plates, which can metamorphose rocks as well.

3. Classification Like igneous and sedimentary rock, metamorphic rock is grouped as well. Metamorphic rock is classified based on its structure. Metamorphic rocks can either be foliated or unfoliated.

4. Foliated rocks Foliated rocks are layered because the pressure applied to the rock is in one direction. Common examples of foliated rock are schist, gneiss, slate, and phyllite. Can you guess what rock the slate in this picture metamorphosed from?

5. Unfoliated rocks If foliated rocks have layers, what do you suppose is true about unfoliated rocks? Quartzite and marble are common unfoliated rocks. Marble is used in many building applications, but is also a source of calcium carbonate, which is used in paint, toothpaste, plastic, and blackboard chalk.

6. Foliated vs. unfoliated Gneiss, which is foliated Marble, which is unfoliated