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Types of Waves. Seismic Waves. Waves. A wave is just a disturbance that moves through a medium. A medium is any material through which a wave travels. The medium for seismic waves is the Earth. Seismic Waves.
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Types of Waves Seismic Waves
Waves A wave is just a disturbance that moves through a medium. A medium is any material through which a wave travels. The medium for seismic waves is the Earth.
Seismic Waves Seismic waves are the waves of energy that travels through the earth and is recorded on seismographs. There are different types of seismic waves. Body waves P-waves S-waves Surface Waves
Body Waves Traveling through the interior of the earth. Body waves arrive before the surface waves. These waves are of a higher frequency than surface waves.
P waves P waves are primary waves because they arrive at seismic reporting stations first. They have the highest velocity of seismic waves.
P waves These are longitudinal waves. Sometimes called an elastic wave.
P waves The P wave can move through solid rock and fluids, like water or the liquid layers of the earth. It pushes and pulls the rock it moves through just like sound waves push and pull the air. http://www.geo.mtu.edu/UPSeis/images/P-wave_animation.gif
S Waves The second type of body wave is the S wave or secondary wave, which is the second wave you feel in an earthquake. An S wave is slower than a P wave and can only move through solid rock, not through any liquid medium.
S Waves S waves move rock particles up and down, or side-to-side--perpendicular to the direction that the wave is traveling. http://www.geo.mtu.edu/UPSeis/images/S
Surface Waves A seismic wave that travels across the surface of the Earth as opposed to through it Only through the Earths crust. Surface waves usually have larger amplitudes and longer wavelengths than body waves, and they travel more slowly than body waves do.
Surface Waves Though they arrive after body waves, it is surface waves that are almost entirely responsible for the damage and destruction with earthquakes. http://www.geo.mtu.edu/UPSeis/images/Love_animation.gif http://www.geo.mtu.edu/UPSeis/images/Rayleigh_animation.gif
How can scientists tell where the earthquake happened? Scientists then use a method called triangulation to determine exactly where the earthquake was. The epicenter is the point on the Earth where the earthquake originated.
The Benefits of Earthquakes Earthquakes relieve the tension between tectonic plates. Little earthquakes help us be not as likely to have bigger ones. Earthquakes shape and move our land. Earthquakes create new land.