Earthquakes are the sudden release of energy stored in the earth’s crust. The energy causes ground and building shaking that can last seconds to a few minutes or more. The point where an earthquake starts below the surface is called a fault and the location on the surface directly above it is known as the epicenter.
Tectonic plates are like puzzle pieces covering the Earth’s skin. They scrape, bump and drag against each other at their edges, where they stick together like the rough edges of an eggshell. Sometimes the plates get stuck at one of the rough edges – and an earthquake happens. When an earthquake occurs, it releases energy in the form of seismic waves. These waves move through the Earth’s layers, including water and air, and shake everything on the ground or in buildings.
While we can’t predict when an earthquake will happen, it is possible to detect signs of a quake before it strikes. People can feel unusual ground movement, notice cracks in the road or walls and see clouds of dust forming. Scientists have also found that a certain kind of radioactive gas, radon, is released into the air shortly before an earthquake.
During an earthquake, it’s important to stay calm and take protective actions. Getting low to the ground, under something sturdy (like your desk) and holding on will help you protect yourself from falling objects. If you can, get away from buildings and power lines as they may fall during an earthquake.