Question

Which of the following statements about seismic waves is false?

1. seismic waves can be reflected when they encounter boundaries between rock layers that possess different acoustic impedance values
2. seismic waves can be refracted (bent) when they encounter boundaries between rock layers that possess different acoustic impedance values
3. S waves cannot travel through liquids
4. seismic waves are useful for identifying rock layers within the Earth
5. S waves and P waves typically travel at the same velocity

Answer 1

The false statement about seismic waves is that S waves and P waves typically travel at the same velocity; they actually travel at different speeds, with P-waves being faster.

Step-by-step explanation:

The statement about seismic waves that is false is: 5. S waves and P waves typically travel at the same velocity. In reality, P-waves (primary or pressure waves) and S-waves (secondary or shear waves) travel at different speeds through the Earth's interior. P-waves, being longitudinal, can travel through both liquids and solids, and move faster, typically at speeds of 4 to 7 km/s. S-waves, on the other hand, are transverse waves and can only move through solids, not liquids, with their speeds ranging from 2 to 5 km/s.

This difference in velocity between P-waves and S-waves is critical for seismology, as it helps in determining the distance to the epicenter of earthquakes and provides insights into the nature of Earth's core, as established by seismographic analysis from scientists like Richard Dixon Oldham and Inge Lehmann.