The earth moves The ground beneath our feet feels solid, but when an earthquake strikes, it starts to shake. If the earthquake is powerful enough, it can be very dangerous. Roads may be torn apart, buildings could collapse and whole cities can be destroyed in minutes. There are more than 500,000 earthquakes every year, but only 100,000 of those can be felt above the ground. Around 100 of these earthquakes cause a lot of damage, especially in towns and cities. It’s these earthquakes that are most dangerous for people.
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So why do some parts of the world have many earthquakes? And what’s it like to live in an earthquake zone?
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The Earth’s crust is made up of tectonic plates that fit together like the pieces of a jigsaw puzzle. The plates lie on top of molten lava, and move very, very slowly at a rate of a few centimetres a year. The plates meet at boundaries called faults. The edges of the plates grind together as the plates move, and sometimes the edges get stuck. Pressure builds up until they suddenly unstick. This causes an earthquake. The grey lines on this map show where the tectonic plates meet. The red dots show the sites of major earthquakes.
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plates
fault plate movement
epicentre
focus
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