Earthquakes are violent shaking from the planet's surface, according to AccuWeather. They're caused by movement from Earth's outermost layer, the crust.
The crust is broken up into pieces called tectonic plates that are always on the move, though usually in ways we cannot feel. When the plates hit a roadblock, stress builds and leads to cracks in the Earth called faults.
In time, the energy from within builds to the breaking point. That sudden release leads to an earthquake.
The shaking begins at a central region called the epicenter and spreads far and wide. An earthquake can then be followed by additional shaking known as an aftershock.
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