In refraction seismology, energy waves travel through which of the following?

In refraction seismology, energy waves travel through which of the following?

• A. Subsurface structures
• B. Atmosphere
• C. Ocean surface
• D. Earth's core

Answer: (A)

Seismic refraction uses energy that travels through the solid rock in the Earth's subsurface. In this method, waves move through different rock layers, and when a wave traveling in a lower-velocity layer reaches a boundary with a higher-velocity layer, it is refracted and can return to the surface as a head wave. By recording the arrival times of these refracted waves at many detectors, we infer the depths to layer boundaries and map the subsurface structures. The atmosphere or ocean surface aren’t the primary media for this propagation, and while waves do exist in those environments, they’re not what refraction seismology relies on. Core waves aren’t typically what this method targets, as surface refraction surveys focus on near-surface to intermediate depths.

Seismic refraction uses energy that travels through the solid rock in the Earth's subsurface. In this method, waves move through different rock layers, and when a wave traveling in a lower-velocity layer reaches a boundary with a higher-velocity layer, it is refracted and can return to the surface as a head wave. By recording the arrival times of these refracted waves at many detectors, we infer the depths to layer boundaries and map the subsurface structures. The atmosphere or ocean surface aren’t the primary media for this propagation, and while waves do exist in those environments, they’re not what refraction seismology relies on. Core waves aren’t typically what this method targets, as surface refraction surveys focus on near-surface to intermediate depths.