1. How a little bit of heat & pressure transform rocks!
Metamorphic Rocks
How a little bit of heat & pressure transform rocks!

2. Metamorphic Rocks The term "metamorphic" means "to change form."
The mineral composition of the rock must change for the rock to become metamorphic.
Gneiss on top
Slate on bottom

3. 1) What is a metamorphic rock?
Rocks buried deep in the Earth at high temperatures and pressures form new minerals and textures all without melting.

4. 2) What types of rocks can undergo metamorphism?
Any rock (igneous, sedimentary, or metamorphic) can become a metamorphic rock.

5. Other rocks are exposed to high heat & pressure
To change form

6. 3) Where do rocks become metamorphic?
Deep within the Earth.

7. 4) What is contact metamorphism?
When a rock comes in contact with a heat source, such as a magma pool.
The hot magma changes a narrow section of the surrounding rock.
Hornfels

8. Click on link and scroll down for nice pictures of metamorphic rocks.

9. 5) What is regional metamorphism?
Occurs in areas with higher heat and pressure. Larger areas are affected.
Usually occurs as a result of the Earth’s plates colliding or moving.

10. 6) What are the two textures of metamorphic rock?
Classified according to its composition and texture.
Foliated
Nonfoliated.

11. Foliated Non-Foliated Other rocks are exposed to high heat & pressure
To change form
Other rocks are exposed to high heat & pressure
Foliated
Non-Foliated

12. 7) What are foliated metamorphic rocks?
Minerals have been flattened and pushed down into parallel layers.
The bands in foliated metamorphic rock look like pages in a book.
Slate
Gneiss

13. Flattened & pushed into parallel layers
To change form
Other rocks are exposed to high heat & pressure
Foliated
Non-Foliated
Flattened & pushed into parallel layers
slate
gneiss
Phyllite

14. 8) What are non-foliated metamorphic rocks?
Do not display layers.
Massive structures with no obvious banding.
Mineral grains grow and rearrange, but they don’t form layers.
Quartzite
Marble

15. Flattened & pushed into parallel layers
To change form
Other rocks are exposed to high heat & pressure
Foliated
Non-Foliated
layers
Anthracite coal
Flattened & pushed into parallel layers
Quartzite
slate
gneiss
marble
phyllite