Everything YOU Need to Know About VOLCANOES

1. Everything YOU Need to Know About VOLCANOES Power Point Lesson

2. Unit Introduction • After watching the video Pompeii – Buried Alive: • Pretend you are a resident or visitor of Pompeii on August 24, 79 AD. Write at least 3 full paragraphs(intro/body/closing)describing: • Who you are (character) • What you are witnessing • How you are feeling / seeing / experiencing • How you plan to survive • Make this creative and fun (…also school appropriate) • You will be reading it aloud to the class • See rubric for grading

4. Volcano Objectives: - Review Earths Composition - Describe how volcanoes form - Describe Hazards - Explain why hazards are deadly - Review Deadliest volcanoes sheet - Examine Mt.St.Helens Eruption - Describe patterns of volcanic activity

5. Lesson 1 Objectives – After today YOU should know • Details of earth’s characteristics • Mechanical • Compositional What are the layers? Describe the characteristics of the layers. • Heat Engines • What are they? • What do they do? • What does this have to do with volcanoes?

6. Lesson 1 • DO NOW: If you could dig your way to China, describe in 5 lines what you would encounter along the way.

7. WHAT YOU ALREADY KNOW… • Red hot MAGMA is in the asthenosphere • The asthenosphere lies below the lithosphere • Material there is molten viscous with increased plasticity

9. Compositional Layers…, what it’s made of! • Crust 5-70 km thick; solid & brittle. • On Saturday a flaming cat nearly killed me. • Continental crust is thick and lightweight (granite or sometimes called silicic b/c of the high silica content) • Oceanic crust is thin and dense (basaltic) • Mantle 2,900 km thick; dense iron rich materials. • Core 3,428 km radius; hot dense nickel and iron.

10. Mechanical Layers –based on physical charactistics • Lithosphere 15-300 km, consists of the crust and rigiduppermost mantle; tectonic plates. • Asthenosphere 250 km, solid “plastic” layer, very slowly flowing rock. • Mesosphere 2,550 km, “middle sphere” lower mantle section. • Outer Core 2,200 km, outer shell of core, LIQUID nickel and iron. • Inner Core 1,228 km, SOLID nickel and iron.

11. Earth’s Heat Engines • External (energy from the Sun) • Primary driver of atmospheric (weather) and hydrospheric (ocean currents) circulation • Controls weathering of rocks at Earth’s surface

12. Earth’s Heat Engines • Internal (heat moving from hot interior to cooler exterior) • Primary driver of most geospheric phenomena (volcanism, magmatism, tectonism) COVECTION

13. Convection - Irregular convection cells transfer heat from the Earth’s core to the surface.

14. Internal Heat Engine • Driven by the decay of radioactive isotopes within the core. • When this decay reaches equilibrium…What happens to Earth?

15. Lesson 2 Objectives for this lesson: • Describe how volcanoes form • Know the relationship to plate boundaries • Hot spot formation • Locate volcanic activity on earth. • Ring of Fire • USA • Hot Spots

16. QUIZ “A” FOR MILKSHAKES • Continental Crust • Main rock type - • Made of (2 main) elements • Silica level (high/low) • Felsic or Mafic • Density (high/low) • Temperature (high/low) • Thickness (thick / thin) • Oceanic Crust • Main rock type - • Made of (2 main) elements • Silica level (high/low) • Felsic or Mafic • Density (high/low) • Temperature (high/low) • Thickness (thick / thin)

17. BONUS- on a separate sheet of paper. • Describe what happened at 3 Mile Island in 5 lines.

19. FIRST DO worksheet • Distribution of Volcanoes on EARTH • Have this done for tomorrow (points) • We will continue notes and review worksheet tomorrow.

21. QUIZ • Are Volcanoes RANDOM? • What is a hot spot volcano? • What is lithospheric subduction? • VIDEO

22. BEFORE WE GO ON: • Continental crust: • GRANITE (SiO RICH, LOW Fe & Mg = FELSIC • Thick • Less dense / More Buoyant • Lower Temperature • Oceanic crust: • BASALT (Fe & Mg RICH, LOW SiO =MAFIC) • Thin • Dense • Higher Temperature

23. SOOOO ….. • WHERE are the volcanoes on EARTH? • Are they random? • What pattern do they most frequently follow? • What OTHER earth activity is associated with these areas?

24. World Location of Volcanoes

25. World Location of Earthquakes

26. Plate tectonics and igneous activity • Global distribution of igneous activity is not random • Most volcanoes are located on the plate margins of the ocean basins (intermediate or andesitic composition) • Second group is confined to the deep ocean basins (basaltic lavas) • Third group includes those found in the interiors of continents

27. How Volcanoes Form • Hot spots Hot spot animation • Subduction of lithosphere • Angry Gods Subduction animation

28. So, How do Volcanoes form? “The Gods are angry. Or the plates along the Ring of Fire are moving again.”

29. Lithospheric Subduction CONVERGENT plate boundaries • Plate collision: causes “slab pull” or subduction • Upon descent : the crust melts • Molten material: rises and creates volcanoes • Name a region

30. Convergent plate boundaries and igneous activity • Rising magma can form • Continental volcanic arcs (Andes Mountains) • Volcanic island arcs in an ocean (Aleutian Islands)

32. Does this look familiar?

34. Ring of Fire

35. Divergent plate boundariesand igneous activity • The greatest volume of volcanic rock is produced along the oceanic ridge system • Lithosphere pulls apart • Partial melting occurs • Produces large quantities of fluid, basaltic magma

36. Divergent plate boundariesand igneous activity • The separating of lithosphere creates trenches and rift valleys. • Examples : Mid Atlantic Ridge ! and the East African Rift Valley

37. Divergent Boundaries

38. TRANSFORM • Plates sliding past each other • San Andreas fault

39. Intraplate igneous activity • Activity within a rigid plate not boundary • Plumes of hot mantle material rise • Forms localized volcanic regions called hot spots • Examples include the Hawaiian Islands and the Columbia River Plateau in the northwestern United States

40. Hot Spots • Hot Spots are magma plumes that rise to the surface • Repeated eruptions builds a volcanic “cone” • Plate moves over the hot spot – creating a chain of islands or an island arc • Name One

41. Ticket out the Door • Where is the most geologically active area in the world? Explain why. • Where in the U.S? Describe the type of plate boundary and reason for the activity. • Is your home at risk? Was it ever? How do you know this?

42. Wrap - up • Review your notes and work with a partner to answer the questions on the last page of skeleton outline. • Educated guesses with justification required to get points.

44. VISCOSITY IS BASED ON COMPOSITION • Continental crust: HIGH VISCOSITY • GRANITE (SiO RICH, LOW Fe & Mg = FELSIC • Thick • Less dense / More Buoyant • Lower Temperature • Oceanic crust:LOW VISCOSITY • BASALT (Fe & Mg RICH, LOW SiO =MAFIC) • Thin • Dense • Higher Temperature

46. Ticket IN the Door • Where is the most geologically active area in the world? Explain why. • Where in the U.S? Describe the type of plate boundary and reason for the activity. • Is your home at risk? Was it ever? How do you know this?

47. Lesson 3 – Unit 4 Objectives for this lesson: • Lab Activity - Topic: How volcanoes are affected by composition. We will review specific objectives after the Lab.

48. DO NOW • Background: The Hawaiian Island eruptions are a tourist attraction, you can go and visit Mt. Kilauea and see the fountains of lava gently spewing from the earth. When Mt. St. Helens erupted in 1980, it killed 9 people and blew half of the mountain off.

49. DO NOW Assignment • Brainstorm with your neighbor. List how the two volcanoes are the same and different. What can you deduce from your findings? After you make your list – analyze the information to make a summarizing statement (1 sentence) explaining what you have concurred.

50. HAWAII Mt.ST.Helens