What’s shaking???

S6E5. Students investigate how the

Earth’s surface is formed

EARTHQUAKES

Def: the vibrations caused by the

breaking of rock within Earth

Where do earthquakes happen?

Along faults(breaks in Earth’s crust)

What causes Faults?

–The movement of plates puts stress on rocks

–After a lot of force, the rocks break and move along the faults

What are the 3 main types of faults?

1 – Normal Faults2 – Reverse Faults3 – Strike-Slip Faults

(Earthquakes!)

How do earthquakes occur?

• Pressure builds up and stresses the rocks

• The rock breaks and moves along the fault

Types of faults depend on the plate boundaries and the stress that moves the rock of the lithosphere.

Most stress is at boundaries where plates meet because…The edges of the plates along faults catch against each other, lock up, stop the movement, and stress builds up!

What are seismic waves?

Waves of energy generated by an earthquake that travel through earth.

What is the epicenter of an earthquake?

The point directly above the earthquake focus is the epicenter or where the earthquake began.

Seismic Waves

The FOCUS is the area beneath Earth’s surface where rock that is under stress breaks, triggering an earthquake.

By predicting where an earthquake is likely to happen…

People can plan their houses to be farther away and/or build seismic-safe structures

• Richter Earthquake Magnitudes Effects:Less than 3.5 Generally not felt, but

recorded. 3.5-5.4 Often felt, but only minor damage. 5.5-6.0 Slight damage to buildings.6.1-6.9 Can be destructive in areas where

people live. 7.0-7.9 Major earthquake. Causes serious

damage. 8 or greater Great earthquake. Total

destruction to close communities.

Earthquake Facts & Games

• http://earthquake.usgs.gov/learn/facts.php

• http://earthquake.usgs.gov/learn/kids/

• http://environment.nationalgeographic.com/environment/natural-disasters/earthquake-profile.html

What happens if there is an earthquake in the ocean?

Tsunamis

A TSUNAMI…HUGE ocean waves created by earthquakes that can destroy everything in the path.

Earthquake Resources:

• http://www.ecs.csun.edu/~shustov/ShakeZone.htm

• http://tlc.discovery.com/convergence/quakes/interactives/makeaquake.html