Understanding earthquakes: The role of Earth's crustal plates

Understanding earthquakes: The role of Earth's crustal plates

John P. Rafferty, biological and earth science editor of Encyclopædia Britannica, discussing the connection between Earth's tectonic plates and earthquake development.
Encyclopædia Britannica, Inc.
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Transcript

[Introduction]

Earthquakes are caused by powerful geologic forces rarely visible on the surface.

[End introduction]

The first thing you need to know about earthquakes is the fact that the Earth is not solid through and through. Basically the ground on which we walk on is divided up into a series of crustal plates that move against one another. An earthquake is caused by the movement of Earth's crustal plates grinding against one another. Since one crustal plate is abutted against another, any movement that occurs is going to cause a grinding or a breakage in one plate or another. And that release of energy is transferred through the rock in all directions to create ripples at the surface, create shaking at the surface, and in many cases, in some cases, even create tsunamis.

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