Locating Earthquake Epicenters

When an earthquake occurs, its energy radiates in seismic waves away from the focus as shown in the diagram above. These waves can be grouped into three categories:


  1. P-waves travel the fastest. These waves vibrate in a push-pull motion through the ground.

  2. S-waves vibrate in all directions perpendicular to the direction of travel.

  3. Surface waves vibrate in a push-pull motion as well as in all directions perpendicular to the direction of travel. These waves cause the most damage as they travel along Earth's surface.

Homework: Due Thursday, December 13th.

Review Book: read pages 54-60. Do questions 1-16.

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