1. Types of Rocks

2. 1. Explain how rocks can be formed? 2. What is the rock cycle? Warm-Up:

3. Describe the texture and composition of the two igneous rocks. A B

4. How to Classify a Rock Rock - A naturally occurring, solid, mixture of one or more minerals or organic matter 3 Groups (based on formation): igneous, sedimentary, and metamorphic Texture and composition give clues as to how rocks are formed, and are used to classify rocks Composition – the type of material a rock contains Texture – the size, shape and arrangement of the minerals/particles that make up a rock. Rocks are always changing form in a cycle called the Rock Cycle

5. Web Links (also found on my website) Rock Cycle Interactive http://www.learner.org/interactives/rockcycl e/index.html Rock Cycle Animations http://www.classzone.com/books/ea rth_science/terc/content/investigations/e s0602/es0602page02.cfm

7. Igneous Rocks Extrusive rocks- formed by cooling lava Texture: glassy (obsidian) porous (pumice) fine-grained (basalt) Intrusive rocks- formed by cooling magma Texture: coarse-grained (granite)

8. Formation of Extrusive Igneous Rock

10. Extrusive Igneous Rock

11. Formation of Intrusive Igneous Rock

12. Intrusive Igneous Rock Yosemite N.P.

13. Obsidian…

14. Basalt…

15. Granite… Course Grained Texture

16. Pumice… Porous Texture

17. Sedimentary Rocks Formed by: Weathering (breaking down of rock) Erosion (movement of sediments) Deposition (collection of sediments) Compaction & Cementation

18. Examples of Weathering Mechanical Weathering Root Action Frost Action Moss

19. Examples of Weathering Chemical Weathering: Oxidation (rock exterior)

21. Five Agents of Erosion Gravity (Mass wasting) Wind Running water Glaciers Waves

22. Gravity (Mass Wasting) Slumping Soil creep

24. Wind

25. Running Water Yellowstone Canyon & River Niagara Falls

26. Glaciers

28. Waves Australia

29. Examples of Deposition Lateral moraine Cape Cod (spit) Nile River Delta

30. Compaction & Cementation

31. Sedimentary Rocks (categorized by composition) Clastic Rocks (rock fragments) Conglomerates (pebbles) Sandstones (sand) Shales (mud & clay) Organic Rocks (once living) Ex: limestone(coral and shells), coal (plants) Chemical Rocks (evaporation) Ex: rock salt, limestone, geodes, gypsum

32. Clastic Sedimentary Rock… Conglomerate Shale Sandstone

33. Organic Sedimentary Rocks… Coal (plant mateiral) Limestone (shell & coral)

34. Chemical Sedimentary Rocks… Limestone Gypsum rock Geode

35. Metamorphic Rocks Formed by tremendous heat & pressure, and chemical reactions inside the crust. Formed from all three rock types.

38. Types of Metamorphic Rock Foliated (bands or layers) Ex: schist, slate, gneiss Gneiss Slate

39. Unfoliated (no bands or layers) Ex: marble and quartzite Types of Metamorphic Rock Quartzite

40. Closure: Describe the texture and composition of the two igneous rocks. A B

41. Warm-up / Closure: 1. In igneous rocks how is cooling rate and crystal size related? 2. Which rock type would you have the best chance of finding a fossil? Why?