Do you know what causes an earthquake? Well today that is just what we are going to talk about.

To understand what causes and earthquake, first we must understand that the Earth`s crust and mantle are made up of large, thin, plates that move on the outer surface of the Earth.
The tectonic plates are always slowly moving, but sometimes, due to friction, they get stuck at their edges. When the pressure on the edges becomes stronger than the friction, these plates slip.

This slipping is what we call an earthquake.The slip releases energy in waves that travel through the earth’s crust and cause the shaking that we feel. Often this slipping occurs at a place that we call a fault, the place where two or more plates touch.

One of the most well know faults is in the state of California, in the U.S.A.
California is where two plates – the Pacific Plate and the North American Plate meet.
The Pacific Plate is made up of most of the Pacific Ocean floor and the California Coast line. The North American Plate is made up of most the North American Continent and parts of the Atlantic Ocean floor.The area along which these two plates touch is called the San Andreas Fault.

The San Andreas Fault is more than 650 miles long and extends to depths of at least 10 miles.The San Andreas Fault produces more than 10,000 earthquakes per year!

Do you know some other areas where faults exists?

Next time we`ll talk about the different types of faults that exist!

See you next time!
Erica

Image of the San Andreas Fault