An earthquake is a violent shaking of Earth's crust. An earthquake is caused by the release of built-up energy along a fault. The energy released depends on how much rock breaks and how far the blocks of rocks move. The surface effects, or intensity, of an earthquake are different from place to place .
Intensity is measured by what can be seen and felt on the surface. What people see and feel often depends on how far they are from the earthquake's focus. The focus of an earthquake is the point right under the fault. Most focus points are less than 72 km below Earth's surface. The point on the surface right above the focus is called the earthquake's epicenter. Here the intensity is the strongest because the seismic waves at the focus is the strongest.
Intensity is measured by what can be seen and felt on the surface. What people see and feel often depends on how far they are from the earthquake's focus. The focus of an earthquake is the point right under the fault. Most focus points are less than 72 km below Earth's surface. The point on the surface right above the focus is called the earthquake's epicenter. Here the intensity is the strongest because the seismic waves at the focus is the strongest.
There are 2 main kinds of seismic waves- body waves & surface waves. Body waves move through the inside of Earth and they can pass through hard rock and liquid. Surface waves move along the Earth's surface.
There are 2 kinds body waves, P waves and S waves. When P waves reach the surface, they cause the rock to move back and forth. When S waves reach the surface, they cause the rock to move up and down.
Surface waves or L waves, travel more slowly than body waves. They do not travel too far from the epicenter of an earthquake. However, surface waves cause the most damage, because they cause the ground to swell and roll over like ocean waves.
There are 2 kinds body waves, P waves and S waves. When P waves reach the surface, they cause the rock to move back and forth. When S waves reach the surface, they cause the rock to move up and down.
Surface waves or L waves, travel more slowly than body waves. They do not travel too far from the epicenter of an earthquake. However, surface waves cause the most damage, because they cause the ground to swell and roll over like ocean waves.
You can measure an earthquake's intensity by the Richter Scale.