• Question: What kind of waves are present during an earthquake?

    Asked by anon-267545 on 11 Nov 2020.
    • Photo: Sam Geen

      Sam Geen answered on 11 Nov 2020:

      Turns out, there are a lot of kinds of waves! https://en.wikipedia.org/wiki/Seismic_wave – things that shake other things can make very complicated wave patterns

      But the main ones are:
      – Primary (“P”) waves which are longitudinal (they compress and expand along the direction of the wave) and travel fastest
      – Secondary (“S”) waves which are transverse (they shake up and down along the direction of the wave) and are a bit slower.

      Geologists can find out about the structure of the Earth from how the waves arrive at different locations, a bit like a medical ultrasound but for the whole planet.

    • Photo: Bradley Young

      Bradley Young answered on 11 Nov 2020:

      There are 3 main types of waves. In longitudinal waves, particles oscillate parallel to the direction of travel of the wave (like sound). In transverse waves, particles oscillate perpendicular to the direction of travel of the wave (like light). In surface waves, particles oscillate in a circular motion (like ocean waves).

      Earthquakes can produce all three of these types of waves

Comments