How do we find the origin of an Earthquake How do we find the origin of an Earthquake? How do we measure the strength of an earthquake?

VIRTUAL EARTHQUAKE

Website: http://www.sciencecourseware.com/virtualearthquake/

Earthquakes – movement of earth’s crust caused by tectonic plates shifting and releasing stored energy Focus – The origin of the earthquake where rocks first break and move Seismograph – instrument used to detect and record seismic waves

P(primary) waves are ______________ than S(secondary) waves Seismic Waves P(primary) waves are ______________ than S(secondary) waves FASTER

Which region of the world did you choose?

Enter your S-P Intervals Seismic Station S-P Interval = seconds Record City and Interval

55 540

HOW CLOSE?

What was the epicenter of your earthquake?

Measuring Amplitude 190

The Richter Nomogram

Enter Your Amplitudes Maximum S Wave Amplitude=

Estimate Magnitude

CONGRATULATIONS. You've done a great job CONGRATULATIONS! You've done a great job. Remember to write down the actual magnitude of your earthquake.

EXPLANATION What is the difference between the epicenter and the focus of an earthquake?

What causes the seismic waves that create Earthquakes?

This happens on a FAULT LINE when the plates: separate from one another (Normal Fault) squish closer together or compress (Reverse Fault) slide alongside one another (Strike-Slip Fault)

What are the three types of seismic waves? 1) P waves – primary waves faster, longitudinal (push & pull) 2) S waves – secondary waves slower, transverse waves (side to side) 3) L waves – love waves when P or S waves hit the surface slowest and most destructive

What scale is commonly used to measure the magnitude of earthquakes? The Richter Scale The Richter scale is a base ten scale. Can anyone explain what that means? A base ten scale means that each integer represents a 10x increase in magnitude from the previous integer.

EVEN MORE! http://videos.howstuffworks.com/howstuffworks/236-how-earthquakes-work-video.htm

ELABORATION ARE EARTHQUAKES THE ONLY TYPE OF NATURAL DISASTER CAUSED BY THE MOVEMENT OF THE EARTH’S TECTONIC PLATES?”