The refraction of P-waves in the mantle is due to:
A) the semimolten state of the mantle.
B) convection.
C) changes in the density.
D) radioactive decays.

Question

Quizplus · Accepted Answer

Refraction of P-waves in the mantle is mainly caused by changes in the density of materials at different depths, which results in the bending of the waves. This is known as the velocity discontinuity or the Lehmann Discontinuity, located at the boundary between the upper and lower mantle. The mantle is mostly solid, so A (the semimolten state of the mantle) and B (convection) are not the primary causes of P-wave refraction. D (radioactive decays) is also not a direct cause of wave refraction.

The Refraction of P-Waves in the Mantle Is Due To