An erathquake happens when two plates crash together. Little earthquakes happen every day. A little earthquake is called a tremor. An earthquake starts deep down in the hypocentre and just above this is the epicentre.
Earthquakes can trigger landslides. Tectonic plates are always moving. Most earthquakes happen on a fault. New Zealand is on the edge of the Pacific and Australian plates. Earthquakes cause vibration waves which are the P-waves and the S-waves. P-waves are short for primary waves and S-waves are short for secondary waves. First ther is a primary wave that gives the shake and the secondary wave follows on.
The primary wave is twenty times faster thasn a jet plane and they go 20 000 kms per hour and the secondary waves go 10 000 km per hour.
Earthquakes are caused by plates moving over, under or past each other. Earthquakes can cause tsunamis.
New Zealand has up to 1500 to 2000 earthquakes every year but hardly any can be felt.
Written by Caitlin Roberts ( aged 7 years)
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