Earthquake

An earthquake is when the ground shakes or spreads apart. Earthquakes occur in the Virgin Islands, Northern and Southern California, Northern and Southern Alaska, and the Alaska Peninsula the most. Earthquakes occur in these areas the most. Earthquakes occur in these areas the most because these areas are on the edges of tectonic plates. My area has a low risk of experiencing an earthquake because Indiana doesn’t have a lot of earthquake history and it isn’t on a tectonic plate boundary.

How do Earthquake Occur

From junior cert you should know that earthquakes occur when two plates slide past each other. (Conservative plate boundary)
In Leaving Cert geography you learn that earthquakes can occur for many reasons.
Activity: Work in pairs and using information from page 30 of your book summarise the main ways in which earthquakes occur.

Earthquake Information

Focus: The point in Earth’s interior where earthquake energy is released.
Epicenter: The point on Earth’s surface directly above an earthquake’s focus.

Causes and Characteristics of Earthquke activity

Earthquake occur mainly on plate bountries that are moving towards, past or away from each other.
Over many years pressure builds up until eventually the rocks snap along a weak called the Fault Line.
The point of origin of an earthquake is the Focus- this is the point where it starts from.
The place at the surface directly above the focus is called the Epicentre.

Seismograph