Seismic Wave Motions—4 waves animated

Novice

An earthquake generates seismic waves that penetrate the Earth as body waves (P & S) or travel as surface waves (Love and Rayleigh). Each wave has a characteristic speed and style of motion. The animations below illustrate both the propogation of the wave as well as the motion of particles as the wave passes. 

Keypoints:

Wave propogation and particle motion for...

  • Body Waves - Primary (P) & Secondary (S) Waves
  • Surface Waves - Rayleigh & Love Waves
P-wave Motion
P-wave:the primary body wave; the first seismic wave detected by seismographs; able to move through both liquid and solid rock. 
Animation Novice
S-wave Motion
S Wave—secondary body waves that oscillate the ground perpendicular to the direction of wave travel. They travel about 1.7 times slower than P waves. Because liquids will not sustain shear stresses, S waves will not travel through liquids like water, molten rock, or the Earth’s outer core. S waves produce vertical and horizontal motion in the ground surface.
Animation Novice
Rayleigh-wave Motion
 Rayleigh Waves—surface waves that move in an elliptical motion, producing both a vertical and horizontal component of motion in the direction of wave propagation.  
Animation Novice
Love-wave Motion
Love Waves—surface waves that move parallel to the Earth’s surface and perpendicular to the direction of wave propagation..
Animation Novice

Related Animations

1-Component Seismogram: Building responds to P, S, surface waves

Seismic waves travel through the earth to a single seismic station. Scale and movement of the seismic station are greatly exaggerated to depict the relative motion recorded by the seismogram as P, S, and surface waves arrive.

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3-Component Seismogram Records Seismic-wave Motion

We use exaggerated motion of a building (seismic station) to show how the ground moves during an earthquake, and why it is important to measure seismic waves using 3 components: vertical, N-S, and E-W. Before showing an actual distant earthquake, we break down the three axes of movement to clarify the 3 seismograms. 

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Seismic Shadow Zone: Basic Introduction

Seismic shadow zones have taught us much about the inside of the earth. This shows how P waves travel through solids and liquids, but S waves are stopped by the liquid outer core.

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Seismic Waves: P- and S-wave particle motion and relative wave-front speeds

The P wave propagates at ~6 km/sec in rock with particle motions that are parallel to the direction of propagation. The S wave is slower at 4 km/sec and propagates with particle motions that are perpendicular to the direction of propagation.

Animation Novice