2. 3 Types of Metamorphism Miss Holl Rowland High School October 24, 2006

3. Outline Regional metamorphism Contact metamorphism Hydrothermal metamorphism

4. Regional Metamorphism Definition Rocks are metamorphosed over large areas that are the size of many states or even several countries

5. Regional Metamorphism Caused by tectonic plates smashing into each other!

6. Regional Metamorphism Conditions High pressure High temperature Plate tectonics Continents collide (smash into each other) Ocean crust subducts

7. Regional Metamorphism Pictures

8. Regional Metamorphism Himalayan Mountains - Continent- Continent Collision!

9. Contact Metamorphism Definition - Hot magma or lava changes (metamorphoses) rocks Can happen deep underground or at the surface

10. Contact Metamorphism Conditions low to moderate pressure (P) –Pressures are generally less than 4 kilobars (Kb) low to high temperature (T) –Temperatures of metamorphism vary widely from 400-1000 Celcius (C)

11. Contact Metamorphism Pictures

12. Contact Metamorphism Pictures

13. Hydrothermal metamorphism

14. Hydrothermal Metamorphism Definition Super-heated ocean water changes rocks Minerals are dissolved or mix with ocean water minerals to form new minerals

16. Hydrothermal metamorphism Conditions Super-heated ocean water emitted from hydrothermal vents on the ocean floor High heat No pressure

17. Hydrothermal metamorphism Pictures

18. Hydrothermal metamorphism Pictures

19. Summary Different conditions create different types of metamorphic rocks High temp, high Pressure - regional metamorphism High temp, low pressure - contact metamorphism Hot water - hydrothermal metamorphism