1. Energy Transformation in the form of Seismic Waves
Earthquakes and waves
Energy Transformation in the form of Seismic Waves

2. New Island
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3. What do you know about Earthquakes?

4. Earthquakes
Earthquakes transfer stored energy into kinetic energy in form of seismic waves.
These waves are MECHANICAL waves
Waves are an oscillation or vibration that transfers energy

5. Earthquake Identification and Location
Earthquakes are located and identified by their focus, epicenter and magnitude
Focus: The point where the fracture in rock occurs, (under ground).
Epicenter: The point, on land, directly above the focus point.
Magnitude: The amount of energy or destruction that has been released/caused

6. Seismographs

7. Seismographs

8. Explain the difference between a Focus and an Epicenter?
If earthquakes are mechanical waves, what are the other types of waves called?

9. Magnitude
Richter Scale: Measures the total amount of energy released by the earthquake.
Magnitude 7 or greater is a major quake
Magnitude 6 or less is a minor quake
Magnitude 2 or less is a micro quake or tremor

10. Magnitude Continued 2. Mercalli Scale:
Measures the degree of destruction that has been caused. This is a scale that is far more subjective in nature.
Mercalli scale rates on a scale of I – XII
(I) is little damage and (XII) is extreme destruction

11. Seismic Waves Primary or P waves Secondary or S waves
Fastest moving seismic wave
Arrive at recording stations first
Moves in a spring like way
Travel through both liquid and solid material
Slower moving wave
Arrives at recording stations after the P wave
Moves in an up and down way
Cause buildings to shake
Travels through solid material only

12. Primary and Secondary Waves
P waves oscillate through compression and expansion, in the same direction of movement
S waves oscillate in a direction that is perpendicular to direction of movement

13. L-Waves L waves are also known as surface waves
They are the slowest but most destructive waves
They are the waves that cause surface rolling

14. Which is the fastest moving seismic wave?
Which seismic wave is most destructive?

15. Distance to Epicenter
Seismologists determine the distance to the earthquake’s epicenter through analyzing the difference in arrival times at the recording station.
When arrival times are close, with little difference, the distance to the epicenter is very small.
The greater the difference in arrival times, the further away the epicenter is
Use information from 3 recording stations to triangulate the location

16. Triangulation

18. Location of Earthquakes
3 major locations where earthquakes occur
Ring of Fire

19. Earthquake location continued
Mid ocean ridges

20. Earthquake locations continued
The Eurasian-Melanesian Mountain Belt

21. What is the different plate activity at each of the locations where seismic activity takes place? Ring of Fire, Mid-Ocean Ridge, and Eurasian-Melanesian Mountain Range