bbc.co.uk/news/world-asia-pacific-12729485

1. The official death toll to about 2,800 but the Miyagi police chief has said that more than 10,000 people are estimated to have died in his province alone. http://www.bbc.co.uk/news/world-asia-pacific-12729485 http://www.youtube.com/watch?v=TRDpTEjumdo http://www.youtube.com/watch?v=AZ5WPXxNzPU

2. Earth’s Interiors

3. How we know what’s inside • Astronomy • Drilling through the crust • Earth’s delivery service -Kimberlite Pipes and Xenoliths -Ophiolites • Seismic data -Vibrational energy waves - Earthquake data

4. Astronomy Calculating Earth’s Density - Gravitational influence, mass - Volume, Shape, Diameter - calc. Density of Earth 5.5 g/cm3 - Surface 2.8 g/cm3

5. Drilling through the crust

7. Describing core. From left to right: Daniele Brunelli (Igneous Petrologist, Centre National de la Recherché Scientifique), Eric Hellebrand (Igneous Petrologist, Max-Planck-Institüt für Chemie), Hiro Tamura Hasebe (Igneous Petrologist, Kanazawa University), Heidi-Elisabeth Hansen (Igneous Petrologist, University of Bergen), Kevin Johnson (Igneous Petrologist, University of Hawaii), Satoko Ishimaru (Igneous Petrologist, Kanazawa University), Natsue Abe (Igneous Petrologist, Japan Marine Science and Technology Center), and Xixi Zhao (Paleomagnetist, University of California, Santa Cruz) in the background. [Photo ID: exp305_006]

8. Drilling through the crust

9. Earth’s delivery service Kimberlite pipe Xenolith

10. Kimberlite Mine in South Africa

14. Seismic Data What causes earthquakes - Elastic rebound theory

15. Seismographs Instrument for measuring magnitude of earthquakes

16. Seismographs

17. Types of Siesmic Waves Body Waves - travel thru the Earth - P waves - S waves Surface Waves- travel around the Earth - Love waves - Rayleigh waves, ground roll

18. P Wave- result from alternating compression and expansion of material

19. P waves: • - primary waves - compressional wave • - movement is in the same direction that the wave is traveling • - highest velocity seismic wave (4mi/s) • - travel through solids, liquids, and gases

20. Earthquake Waves

21. S wave - distortion of material, perpendicular to the direction the wave is traveling.

22. S waves: - secondary waves - transverse or shear waves • - slower than P waves (2mi/s) • - can only pass through solids - slightly greater amplitude than P waves

23. Earthquake Waves

24. Rayleigh Surface Waves Love

25. Surface Wave: • - a seismic wave that travels along the surface of the Earth Surface Waves: • - dampen quickly, don't travel very far

26. Richter Scale

27. Modified Mercalli Intensity Scalefrom FEMA I. People do not feel any Earth movement. II. A few people might notice movement if they are at rest and/or on the upper floors of tall buildings. III. Many people indoors feel movement. Hanging objects swing back and forth. People outdoors might not realize that an earthquake is occurring. IV. Most people indoors feel movement. Hanging objects swing. Dishes, windows, and doors rattle. The earthquake feels like a heavy truck hitting the walls. A few people outdoors may feel movement. Parked cars rock. V. Almost everyone feels movement. Sleeping people are awakened. Doors swing open or close. Dishes are broken. Pictures on the wall move. Small objects move or are turned over. Trees might shake. Liquids might spill out of open containers.

28. VI. Everyone feels movement. People have trouble walking. Objects fall from shelves. Pictures fall off walls. Furniture moves. Plaster in walls might crack. Trees and bushes shake. Damage is slight in poorly built buildings. No structural damage. VII. People have difficulty standing. Drivers feel their cars shaking. Some furniture breaks. Loose bricks fall from buildings. Damage is slight to moderate in well-built buildings; considerable in poorly built buildings. VIII. Drivers have trouble steering. Houses that are not bolted down might shift on their foundations. Tall structures such as towers and chimneys might twist and fall. Well-built buildings suffer slight damage. Poorly built structures suffer severe damage. Tree branches break. Hillsides might crack if the ground is wet. Water levels in wells might change. IX. Well-built buildings suffer considerable damage. Houses that are not bolted down move off their foundations. Some underground pipes are broken. The ground cracks. Reservoirs suffer serious damage.

29. X. Most buildings and their foundations are destroyed. Some bridges are destroyed. Dams are seriously damaged. Large landslides occur. Water is thrown on the banks of canals, rivers, lakes. The ground cracks in large areas. Railroad tracks are bent slightly. XI. Most buildings collapse. Some bridges are destroyed. Large cracks appear in the ground. Underground pipelines are destroyed. Railroad tracks are badly bent. XII. Almost everything is destroyed. Objects are thrown into the air. The ground moves in waves or ripples. Large amounts of rock may move.

30. Liquefaction

31. Liquefaction A phenomenon in which the strength and stiffness of a soil is reduced by earthquake shaking.

32. Niigata, Japan 1964

33. Sand boil

34. 1989 Loma Prieta Liquefaction induced road failure

36. Tsunami

37. Travel of Seismic Waves • In homogeneous material, they travel in a straight line. When seismic waves encounter a boundary, they will reflect or refract.

38. Homogeneous Heterogeneous

39. Reflection – return of wave off a boundary (bounce back) Refraction – change in direction and velocity of the wave

40. Bedrock vs. Unconsolidated Sediments

41. We hypothesize that the outer core is molten because S waves will not pass through it. Seismic Shadow Zones

42. S-Wave Shadow Zone

43. P-Wave Shadow Zone

44. P-Wave Shadow Zone

45. Seismic Discontinuities We hypothesize that the asthenosphere is partially molten because seismic waves slow down when they enter it.

46. Earth’s Layers

47. How do we know exactly where an earthquake occurs?