1. Seismology is the study of
Earthquakes

2. Earthquake in
Turkey in 2001
buckled railroad ties

3. Armenia Earthquake 1988

4. Great Alaska
Earthquake
1964
8.9

5. East Coast Earthquake 5.8

6. Mercalli
Damage Scale

7. Richter Scale - each increase of 1 represents 10 times
more energy

8. 9.0 Sumatra 2004
8,9 Japan 2011
8.8 Chile 2010
7.0 Haiti 2010
5.8 Virginia 2011

10. focus animation

11. Earthquakes produce 3 types of waves
Ground roll
P wave

12. wave motion 1
p wave motion
s wave motion

13. Differences between “P” and “S” waves
P Waves travel almost twice as fast
P waves travel through liquids and solids
P waves all called primary waves or push -pull -waves
S waves cannot travel through liquids
S waves provide evidence for a liquid outer core
S waves are called shear waves or secondary waves

14. L waves (or ground roll) can be the
Biggest. They travel along the surface and
Cause a lot of the surface damage

15. P and
S waves
travel
throughout
the earth

16. When the waves enter
a zone of sharply
differing density, they
are bent or refracted.
This causes
SHADOW
ZONES

17. refraction
shadow zones
shadow zones 2

18. The waves are received on a seismograph

20. Seismometer

22. Simplified version of seismographs

23. Most earthquakes
occur along
ACTIVE FAULTS
at tectonic plate
boundaries

24. Pacific Plate
San Andreas Fault
N. American Plate

25. Socal Earthquakes

27. A branch of the San Andreas
Fault running across highway

28. Earthquake along
San Andreas Fault