Earthquakes The Great Shake-Out!!!!

You need to write this down!! What are Earthquakes? The shaking caused by the sudden release of energy Caused by faulting (breaking) at plate boundaries

Collapsed Cypress Freeway Source: Richards/Sipa Press

Effects of Mexico City Earthquake Source: Albert Copley/Visuals Unlimited Copyright © Houghton Mifflin Company. All rights reserved.

Where Do Earthquakes Occur and How Often? ~80% of all earthquakes occur in the ring of fire around the pacific plate. ***more than 150,000 quakes strong enough to be felt are recorded each year

Seismic Risk Map

Anatomy of an Earthquake Copyright © Houghton Mifflin Company. All rights reserved.

What causes Earthquakes? 1. Movement along faults: occurs when the energy exceeds the friction holding the sides of the fault together and is suddenly released. This is the Elastic Rebound Theory. 2. Movement of magma (volcanic) 3. Volcanic eruptions

Landscape Shifting, Wallace Creek Source: John S. Shelton Copyright © Houghton Mifflin Company. All rights reserved.

Seismic Waves 1. P or primary waves fastest waves travel through solids, liquids, or gases Compression wave, material movement is in the same direction as wave movement 2. S or secondary waves slower than P waves travel through solids only Transverse waves - move material perpendicular to wave movement

P Waves Copyright © Houghton Mifflin Company. All rights reserved.

How do we Measure Earthquakes? P-waves, S-Waves, and Surface waves occur after an earthquake Earthquake waves are recorded by a seismograph and the recording of waves on paper is called seismogram

Earthquake Dangers 1. Falling objects and most property damage results from 2. Fires that start after the earthquake is over because of broken GAS LINES 3. Tsunami-seismic sea wave 4. Landslides

Earthquake Dangers A. Most injuries and deaths are caused by falling objects and most property damage results from fires that start from broken gas lines. B. Tsunami: seismic sea wave sometimes generated when an earthquake originates on the ocean floor

Generation of a Tsunami Copyright © Houghton Mifflin Company. All rights reserved.

Tsunami—December 2004 http://www.bedford.k12.ny.us:16080/flhs/science/images/tsunami2004/

NSF North Mississippi GK-8 Who Feels the Shaking? The shaking starts at the epicenter and spreads in circles outward much like the ripples of water dripping into a puddle. NSF North Mississippi GK-8

Elevated Freeway Collapse in Kobe Source: Hosaka Naoto/Gamma Liaison Copyright © Houghton Mifflin Company. All rights reserved.

8. Earthquake Dangers 4. Landslides

Earthquake Safety Protect yourself from falling objects (GET UNDER SOMETHING) or stand in a hallway or doorway (watch out for a swinging door) Do not try to go outside during the earthquake After the earthquake and before the aftershocks, go outside Do not return to the building until it has been inspected

Making Homes Safer Attach bookcases and tall furniture to the wall Reinforce chimney Strap water heater to the wall Bolt houses to the foundation Reinforce walls with extra wood Keep a wrench handy to turn off gas lines

Earthquakes rarely kill people … Building collapses do! Interesting Facts Earthquakes rarely kill people … Building collapses do!

The Great SHAKE OUT! Your group will design a structure made out of toothpicks and marshmallows that can withstand a simulated earthquake. You will get 15 toothpicks and 10 marshmallows— don’t eat them. Copy the engineering and design process into your notes. Plan and draw a sketch of your design Test the structure Re-design and sketch your new updated structure Retest your structure

Draw this in your notes: DESIGN PROCESS