Earthquakes.......

Earthquakes are sudden movements in the earth’s crust that cause tremor's or vibration's. They, like volcanoes, usually occur along the edges of the plate boundaries; these edges are called fault lines . When the plates collide or rub against one another this will cause and earthquake.Focus is the word used to describe the spot within the earth’s crust where the earthquake begins. The epicentre is the place on the earth’s surface directly above the focus. Shock waves are sent out from the epicentre and focus and they cause the major damage often associated with earthquakes. The nearer to the epicentre themore severe the damage.

A seismograph is the intrument used to record the earthquake and the scale used to measure the strength of an earthquake is called the Richter Scale. This scale ranges from 1-12 and each step.