4. Sedimentary rock forms when sediment is carried away by wind, ice or water and deposited in layers under pressure Sediment is any fragments of rock, minerals or organic materials

5. Common Sedimentary Rocks shale (from fine mud particles) sandstone (sand) conglomerate (gravel) coquina (seashells) limestone (precipitates or tiny skeletons)

6. Cementation Compaction

7. sedimentary rock is formed from pieces of smaller rock sedimentary rock is formed from pieces of minerals sedimentary rock is formed from pieces of the remains of living things

8. Igneous rock develops when magma comes through the crust and cools Intrusive rock forms underground Extrusive rock forms on the surface

9. Cooling Solidifying

10. Igneous texture Depends upon crystal size Depends upon crystal size Slower cooling produces larger crystals Slower cooling produces larger crystals Rocks cool slowly if formed deep in Earth Rocks cool slowly if formed deep in Earth Lava cools more quickly, has smaller crystals Lava cools more quickly, has smaller crystals Some common igneous rocks are- Some common igneous rocks are-

11. Common Igneous Rocks Obsidian – smooth volcanic glass Obsidian – smooth volcanic glass Basalt- dense rock of ocean floor Basalt- dense rock of ocean floor Granite- lighter rock of continents Granite- lighter rock of continents Pumice- porous volcanic rock Pumice- porous volcanic rock

12. Metamorphic rock is formed when heat, pressure and chemical reactions change one type of rock into another.

15. Heat and Pressure

16. metamorphism happens when rock comes into direct contact with magma below the surface metamorphism happens when a large area of rock is heated due to plate collisions

17. Common Metamorphic Rocks Marble from limestone Quartzite from sandstone Slate, phyllite, schist, and gneiss from shale

18. Any type of rock can be changed into any of the other types of rock by natural forces.

19. Weathering Erosion

20. Intense Heat Pressure

21. Melting

23. Review Questions 1. What are three major types of rock found in nature? 2. All new rock starts out as what type of rock? 3. What is the difference between intrusive and extrusive igneous rock?

24. Review Questions 4. How are sedimentary rocks formed? 5. Describe the three types of sedimentary rock. 6. What three types of forces are present when metamorphic rock forms?