Earthquake Destruction

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.

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 2 3 4 5 10 times 10 times 10 = 1000

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

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!!

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

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.

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

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

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

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

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

Pictures of Damage

1906 – San Francisco

1906 – San Francisco

1906 – San Francisco – 700- 3000 dead

Pakistan – October 2005

Pakistan – killed nearly 25,000 people

Sichuan Earthquake – 2008

Sichuan Earthquake – 2008 Death Toll – Over 55,000

Stop Disasters and Save a Town! www.stopdisastersgame.org/en/home.html 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.

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