Earthquakes
About Earthquakes
What is an earthquake?
An earthquake is what happens when two blocks of the earth suddenly slip past one another. The surface where they slip is called the fault or fault plane.
P-waves: Longitudinal waves from an earthquake are called primary waves because they are the first waves to arrive in an area at any distance from the epicenter. They travel faster than other waves because the movement of the wave is parallel to the direction the wave is traveling as it moves away from the epicenter. These waves can also travel through liquid, solids, and gasses. This is how we can determine the structure of the Earth.
S-waves: S waves also called secondary waves and shear waves, are the second waves to hit the seismographs. They are transverse waves, which means that the motion is perpendicular to the direction of wave propagation. They move side to side perpendicular to the direction the wave travels.
