Which waves are the last to reach the seismic station?

Which waves are the last to reach the seismic station?

• A. P waves
• B. S waves
• C. L waves
• D. Surface waves

Answer: (C)

Waves that travel along the Earth’s surface move more slowly than those moving through the interior, so they arrive later at a seismic station. After the fast body waves (P waves) and the slower body waves (S waves), the energy that stays near the surface—Love waves, along with Rayleigh waves—propagates the slowest. Because of their lower speed and surface-path propagation, these surface waves arrive last. That’s why Love waves (L waves) are the correct choice for the last-to-arrive waves.

Waves that travel along the Earth’s surface move more slowly than those moving through the interior, so they arrive later at a seismic station. After the fast body waves (P waves) and the slower body waves (S waves), the energy that stays near the surface—Love waves, along with Rayleigh waves—propagates the slowest. Because of their lower speed and surface-path propagation, these surface waves arrive last. That’s why Love waves (L waves) are the correct choice for the last-to-arrive waves.