Earthquakes

1. Review Test Me Earthquakes Types of Faults Where do they Occur? The Film Earths Structure Predictions Measuring

2. Review Test Me Where do they occur? Plate Tectonics Hazard Zones

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4. Test Me World Plate Boundaries Transform plate boundaries Divergent Plate Boundaries Click for a detailed map Boundary Table Convergent plate boundaries

5. Review Test Me Table of Tectonic Plate Boundaries Back to Plate Tectonics

6. Review Test Me Divergent Plate Boundaries where two plates move away from each other . Most of the world's divergent plate boundaries are on the ocean floor, in the form of mid-ocean spreading ridge. At divergent boundaries, the two plates are continually moving apart, heading in opposite directions away from each other. Divergent Illustration Back to Plate Tectonics

7. Review Test Me Divergent Plate Illustration Mid-Ocean spreading in the deep ocean basins where the plates move apart. As they separate, hot lava from the mantle rises between them. This lava gradually cools, contracts, and cracks, creating faults. Most are shallow Back to Plate Tectonics

8. Review Test Me TransformPlate Illustration Where plate slide horizontally against each other. These can also be caused by soil liquefaction (where the soil acts like liquid) Back to Plate Tectonics

9. Review Test Me Transform Plate Boundaries Where two plates move horizontally side-by-side in opposite directions. Transform plate boundaries are strike-slip faults. As the two plates slide next to each other, trying to move in opposite directions, there is much friction and stress between them. As a result, transform plate boundaries are zones of frequent earthquakes. Transform Plate Illustration Back to Plate Tectonics

10. Review Test Me • Convergent plate boundaries Where two plates move toward each other and either collide with each other or one plate bends down and goes beneath the other. Convergent plate animation Back to Plate Tectonics

11. Review Test Me • Convergent plate Illustration Called Sub-duction zones these comprise approximately 80% of major quakes. The famed Ring of Fire is included. One plate is thrust under another. Back to Plate Tectonics

12. Review Test Me Areas with frequent activity The famed Ring of Fire Hazard Zone Steps to Safety

13. Review Our Violent Home

14. Review Test Me Public Domain • Make an earthquake preparedness kit! • Food, water, matches, flashlight, batteries, blankets and SHOES! All will be very hard to come by following a large earthquake! Safety Take action during an earthquake and remember to ‘Drop’, ‘Cover’ and ‘Hold On’. Move outside and away from buildings after the shaking. Back to Hazard Zone

15. Review Test Me Earths Structure Compositional Layers Mechanical Layers

16. Review Test Me Crust Compositional Layers Mantle Core Back to Earths Structure

17. Review Test Me Lithosphere Mechanical Layers Aesthenosphere Inner Core Outer Core Back to Earths Structure

18. Review Test Me Crust The outer layer of the Earth. Continental crust is thick (25-50 km thick), low in density, and has an intermediate average composition. Oceanic crust is thin (typically 5-10 km thick), higher in density, and has a mafic average composition Back to Earths Structure

19. Review Test Me Mantle The layer located above the Core and below the Crust it begins about 6 miles(10 km) below the oceanic crust and about 19 miles (30 km) below the continental crust. It is about 1,800 miles (2,900 km) thick and makes up about 80% of Earth’s total volume Back to Earths Structure

20. Review Test Me Core Although we have no samples to look at Seismic waves suggest a very dense molten metallic core. Back to Earths Structure

21. Review Test Me Outer Core Is scorching hot and electrically conductive liquid. It is where Earth’s magnetic field is generated. Back to Earths Structure

22. Review Test Me Lithosphere which is a rigid layer that is broken up into tectonic plates and averages about 100 km (60 miles) thick. Back to Earths Structure

23. Review Test Me Aesthenosphere The layer beneath the lithosphere is the weak, soft Aesthenosphere, which is roughly 300 to 400 km thick Back to Earths Structure

24. Review Test Me The vibrations produced by earthquakes are detected, recorded, and measured by instruments called seismographs.  The line made by a seismograph, called a "seismogram," show the changing intensity of the vibrations by responding to the motion of the ground. From this scientists can determine the time, the epicenter, the focal depth, and the type of fault of an earthquake. There are two main types of scales used in connection to Earthquakes. The Mercalli and the Richter. Measuring Earthquakes The Mercalli Scale The Richter Scale

25. Review Test Me The Richter Scale In 1935, Charles F. Richter devised a way to record quake activity by measuring the size of the seismic waves caused by the shifting earth. These impressions are recorded on a device known as a seismograph, and much can be told from this mechanism. This graph can measure the date and time, along with the exact central location of these troubling disasters. They in turn, are then ranked in terms of severity on the world famous

26. Review Test Me The Mercalli Scale One way to measure the strength of an earthquake is to use the Mercalli scale. Invented by Giuseppe Mercalli in 1902, this scale uses the observations of the people who experienced the earthquake to estimate its intensity. .

27. Review Test Me Predictions Scientist use past occurrences to determine the likelihood of quakes. Very little improvement has been made in the accuracy of these predictions over the last half century.

28. Review Test Me Whose Fault is it? The crustal plates are being deformed by stresses . The ground will first bend, then upon reaching a certain limit, breaks and “snaps” to a new position. There are a couple main types of faults which cause earthquakes. Strike-Slip Fault Dip-Slip Fault

29. Review Test Me Strike-Slip faults move horizontally and form from Shear stress. Strike-Slip Fault Strike-Slip Fault Animation Back to Faults

30. Review Test Me Dip-Slip faults move vertically. One side moves up while the other moves down. Dip-Slip Fault Dip-Slip Fault Animation Back to Faults

31. Review Test Me Strike-Slip FaultAnimation Back to Faults

32. Review Test Me Dip-Slip FaultAnimation Back to Faults

33. Review Test Me Back to Measuring

34. Review Test Me Back to Measuring

45. Review Test Me Devastation The Film

47. Quiz Question 1 The Mashall Scale Which of the below is a way to measure earthquake intensity? The Mercury Scale The Mecalis Scale

48. † Both the Mercalli and Richter scale are used to Measure Earthquakes. † Two plates moving horizontally (side by side) form Transform boundaries and are active areas for Earthquakes. † Stop Drop and Cover! Is the safety motto for Quake preparedness † There are 3 major plate environments on Earth. Review † The Lithosphere is 60 miles thick and is where most earthquakes occur.

49. † Mid-Ocean Ridges form from Divergent boundaries. † Nearly 80% of major Quakes form from Convergent boundaries † The crust forms a thin outer layer on Earths surface. † Earthquake prediction has not changed much over the last 20 years. † What we have learned about the core is not from direct observation . Review † What we have learned about the core is not from direct observation .

50. Quiz Question 2 2 4 3 How many Major types of Plate environments exist?