Seismic Waves are waves of energy caused by sudden movement within the earth. They travel through the earth and are recorded on seismographs.
There are various different types of seismic waves, and they move in different ways. There are 2 main types of waves, they include body waves and surface waves.
There are various different types of seismic waves, and they move in different ways. There are 2 main types of waves, they include body waves and surface waves.
Body Waves
Travelling under the earth, body waves are emitted before surface waves. Body waves have a higher frequency than surface waves.
P Waves
Primary Waves are the fastest kind of seismic waves and the first to be recorded on a seismometer. Primary waves can move through solid rock and fluids. It pushes and pulls the rocks it moves through causing the rocks to deform. Sometimes animals can hear the P Waves of an earthquake. Most commonly, Dogs begin barking fiercely just before an earthquake strikes. P waves are also known as compressional waves, because of the pushing and pulling.
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S Waves
The second type of body wave is the secondary wave. A Secondary wave is slower than a primary wave and can only move through solid rocks and not through any liquid. This property of secondary waves led seismologists to conlude that the Earth's outer core is a liquid. Secondary waves move rock particles up and down,
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Surface Waves
Surface Waves travel only through the crust and are of a lower frequency than body waves. As a result, they are easily distinguished on a seismograph. Even though surface waves arrive after body waves, Surface waves are responsible for the damage and destruction related to earthquakes.
Rayleigh Waves
The Second type of surface wave is the Rayleigh wave. Named after John William Strutt, Rayleigh waves roll along the ground. Due to this behaviour, it moves the ground up and down, and side to side in the direction of the wave. Most of the "shaking" felt during an earthquake is from a Rayleigh wave.
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