1. Earthquake Destruction

2. Richter Scale
A scale that measures the magnitude of the largest wave recorded on the seismogram.
The wave amplitude increases by 10 for every 1 magnitude increase on the scale.
A Magnitude 3 has waves 10 times bigger than a Magnitude 2.

4. Richter Scale 1000 times stronger
How many times stronger is an earthquake that measures 5 on the Richter Scale than an earthquake that measures a 2?
1000 times stronger
10 times times 10 =

7. Earthquake Destruction
Damage to buildings and other structures
(bridges, roads) depends mainly on 3 things:
1. Magnitude of earthquake waves and duration of earthquake
The stronger and longer the earthquake, the more damage it will do

8. Earthquake Destruction
2. Building & structure design – HOW was the building designed and constructed?
Steel-frame buildings CAN resist seismic waves
Unreinforced stone/brick buildings CANNOT!!

9. Elevated Highways: A Common Problem
Too much weight on concrete columns!

10. Earthquake Destruction
3. The type of ground that the buildings & structures are built on top of
Liquefaction – ground becomes saturated with water and turns like quicksand
Can’t support the structures that are on top
Buildings sink & collapse
Gas, water & sewage lines underground can rise out of the ground and break.

12. Other Types of Damage Tsunami – seismic sea waves
~often called ‘Tidal Waves” but they are NOT caused by the tidal effects of the moon or sun
~caused by underwater earthquakes
As waves near the shore, the water slows down and piles up on itself – waves reach heights of 30 meters and can go as fast as 50km/hr

13. 12/26/2004 - Tsunami hit Sumatra because of the 3rd most powerful Earthquake recorded since 1900.

19. Another Video of Japan - BBC link
Japan’s Tsunami after the 4th Most Powerful Earthquake on Friday, March 11th
Watch Video
Another Video of Japan - BBC link

20. Fire
Fire starts when gas or electrical lines are broken during an earthquake
~harder to put out because water lines are often also broken during an earthquake

21. Landslides The sinking of ground triggered by earthquake vibrations
Can cause foundations of buildings or even ENTIRE buildings to collapse
Can rupture gas, water or sewer lines

22. Pictures of Damage

23. 1906 – San Francisco

24. 1906 – San Francisco

25. 1906 – San Francisco – dead

26. Pakistan – October 2005

27. Pakistan – killed nearly 25,000 people

28. Sichuan Earthquake – 2008

29. Sichuan Earthquake – 2008
Death Toll – Over 55,000

31. Stop Disasters and Save a Town!
For extra credit…visit this website and play the game.
Print out your results. If they are good enough (meaning you saved enough people and property) I will give you extra credit points
When you complete the activity, write a paragraph summary of what you did to save the town and why or why not it was successful.

32. Seismic Risk in U.S. Expected : California, Washington
Unexpected : Florida, North Dakota, Minnesota
Seismic Risk is developed by looking at the history of the area