Vocabulary #13 (Earthquakes)

Definitions:

1. fault: a huge crack in the crust, at or below the surface, the sides of wich may show evidence of motion
2. focus: the point where an earthquake starts, where rocks begin to slide past each other
3. seismic wave: a vibration that spreads out away from a focus when an earthquake happens
4. epicenter: the point on Earth's surface directly above the focus
5. aftershock: the shaking of the crust after the initial shaking of an earthquake
6. seismograph: a sensitive device that detects the shaking of the crust
7. magnitude: the amount of energy released by an earthquake

Sentences and illustrations:

1. There are three kinds of faults.

2. The focus is usually bellow the surface.

3. Seismic waves travel trough the crust.

4. Is in the epicenter where people feel first the ground shaking

5. Aftershocks continue the damage of an earthquake.

6. A seismograph shows patterns in the waves that arrive.

7. The height of a wave on a seismograph is a measure of the magnitude.