Teaching Point: “To analyze the anatomy of an earthquake.”
Do now Discussion: How might you react in this situation?
Earthquakes 101 - National Geographic
TP: “To analyze the anatomy of an earthquake.”
Rocks deep underground build up stress along what will become a fault
Earthquakes are Released Stress
TP: “To analyze the anatomy of an earthquake.”
Rocks under stress change shape (i.e. become strained)
More stress = more strain
Stress Leads to Strain
TP: “To analyze the anatomy of an earthquake.”
Rocks can change shape to a point, after which they break.
When rocks break under stress, they release energy waves- an earthquake
Focus = earthquake location underground
Epicenter = point on Earth’s surface above earthquake focus
Parts of an Earthquake
TP: “To analyze the anatomy of an earthquake.”
Worldwide Earthquake Epicenters
TP: “To analyze the anatomy of an earthquake.”
Waves Made By Earthquakes
TP: “To analyze the anatomy of an earthquake.”
Wave Type | Wave Name | Speed | Waves Can Pass Through… |
P- Waves | Primary Waves | Fast | Solids and Liquids |
S- Waves | Secondary Waves | Slow | Solids-only |
Earthquakes make two types of energy body waves
P and S-waves are recorded on pieces of paper called seismograms by a seismograph
P-Wave are Compression Waves
TP: “To analyze the anatomy of an earthquake.”
S-Waves are Shear Waves
TP: “To analyze the anatomy of an earthquake.”
Seismograph Machines
TP: “To analyze the anatomy of an earthquake.”
When the ground underneath the machine shakes, its needle shakes making squiggly lines on the paper
Seismogram Record P and S Wave
TP: “To analyze the anatomy of an earthquake.”
On a seismogram…
No Waves
P-Wave Arrival
S-Wave Arrival
Earthquakes and Earth’s Interior
TP: “To analyze the anatomy of an earthquake.”
When they enter the Earth’s layers, P waves refract (i.e. bend) creating shadow zones
Shadow zones are places on Earth where no seismic waves were detected by a seismograph.
TP: “To analyze the anatomy of an earthquake.”
When they enter the Earth’s layers, S-waves do not pass through the liquid outer core creating a large shadow zone
Earthquakes and Earth’s Interior
S-wave shadow zones are evidence of Earth’s liquid outer core
Richter Scale = measuring absolute magnitude (strength)
Earthquake Measurement Scales
TP: “To connect earthquake strength and plate boundaries.”
Magnitude and Energy Released
TP: “To connect earthquake strength and plate boundaries.”
Mercalli Scale = measuring magnitude by damage
Measuring Earthquakes
Modified Mercalli Scale Animation
TP: “To connect earthquake strength and plate boundaries.”
Mid-Lesson Assessments
TP: “To analyze the anatomy of an earthquake.”
a. P / S
b. S / P
c. P / R
c. S/ L
Lesson Assessment Question
TP: To model the profile of a stream bottom.”
a. reflected
b. transmitted
c. refracted
d. absorbed
Lesson Assessment Question
TP: To model the profile of a stream bottom.”
Regents Assessment Question
TP: To model the profile of a stream bottom.”
a. an interior Earth layer absorbs S-waves
b. Earth’s mantle reflects S-waves
c. S-waves travel slower than P-waves
d. S-waves travel on Earth’s surface
Regents Assessment Question
TP: To model the profile of a stream bottom.”
a. P-waves that travel faster than the S-waves shown in model B
b. P-waves that travel slower than the S-waves shown model B
c. S-waves that travel faster than the P-waves shown in model B
d. S-waves that travel slower than P-waves shown in model B
Intellectual Engagement
Do you think social media platforms like Twitter and Facebook could be used in conjunction with a tsunami warning system?
TP: “To analyze the anatomy of an earthquake.”
Let’s Review in Groups
In your group, go back into your notes and make a list of the three (3) most important concepts we learned today. Place those the three in order from the most important concept to least important.
TP: “To analyze the anatomy of an earthquake.”