Seismic Shadow Zones: P wave

How do P waves give information about Earth's core?

Animation addresses 5 common variations of P-type seismic body waves. All are compressive waves that travel through the Earth in all directions away from the epicenter of an earthquake. The different phases show how the initial P wave changes when encountering boundaries in the Earth


Keypoints:

Information about Earth's deep interior is derived from seismic waves:

  • P waves are compressive body waves that travel through solids and fluids
  • P waves are the fastest seismic waves
  • P waves are refracted at the mantle-outer core boundary
  • P waves can create phase changes as they pass through changing material
  • Phase changes yield information about the unseen interior of the Earth

Total Time: 3min 26s
Level: Novice

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