1. Earthquakes

2. Elastic Rebound The sudden return of elastically deformed rock to its undeformed shape.

3. Anatomy of an Earthquake

4. Seismic Waves Two Main Types of Seismic Waves:
Body Waves: A seismic wave that travels through the body of a medium.
Surface Waves: A seismic wave that travels along the surface of a medium and that has a stronger effect near the surface of the medium than it has in the interior

5. Body Waves
P Waves (Primary Waves): A primary or compression wave; a seismic wave that causes particles of rock to move in a back-and-forth direction parallel to the direction the wave is traveling.
P Waves can travel through solids, liquids, and gases. They travel faster through more rigid material.
S Waves (Secondary waves): A secondary wave, or shear wave; a seismic wave that causes particles of rock to move in side-to-side direction perpendicular to the direction in which the wave is traveling.
S Waves can only travel through solids.
Body waves are the fastest moving waves and the first detected.

6. P Waves and S Waves

7. P Waves – Primary Waves (Compression Waves)

8. S Waves – Secondary Waves (Shear Waves)

9. Surface Waves
Love Waves: A surface wave that cause rock to move side to side and perpendicular to the direction the wave is traveling.
Rayleigh Waves: A surface wave that causes the ground to move with and elliptical, rolling motion
Surface waves are the slowest moving waves and the most deadly and destructive waves.

10. Love Waves and Rayleigh Waves

11. Love Waves

12. Rayleigh Wave Animation

13. Shadow Zones
An area on Earth’s surface where no direct seismic waves from a particular earthquake can be detected.