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

6. 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)

7. Formation of Extrusive Igneous Rock

8. Extrusive Igneous Rock

9. Formation of Intrusive Igneous Rock

10. Intrusive Igneous Rock Yosemite N.P.

11. Obsidian…

12. Basalt…

13. Granite… Course Grained Texture

14. Pumice… Porous Texture

15. Sedimentary Rocks Formed by: Weathering (breaking down of rock)

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

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

18. Sedimentary Rocks Formed by: Weathering (breaking down of rock) Erosion (movement of sediments)

19. Five Agents of Erosion Gravity (Mass wasting)

20. Gravity (Mass Wasting) Slumping Soil creep

21. Five Agents of Erosion Gravity (Mass wasting) Wind

23. Five Agents of Erosion Gravity (Mass wasting) Wind Running water

24. Running Water Yellowstone Canyon & River Niagara Falls

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

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

28. Australia

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

30. Sedimentary Rocks Formed by: Weathering (breaking down of rock) Erosion (movement of sediments) Deposition (collection of sediments)

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

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

34. 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

35. Clastic Sedimentary Rock… Conglomerate Shale Sandstone

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

37. Chemical Sedimentary Rocks… Limestone Gypsum rock Geode

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

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

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

43. Sedimentary Rocks Metamorphic Rocks Igneous Rocks Sediments Magma & Lava Heat Pressure Compaction & Cementation W.E.D. Melting Heat Pressure Cooling W.E.D. = Weathering, Erosion, & Deposition

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

45. 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?