Introduction to Seismic Waves

Seismic waves are energy ripples that travel through the Earth's layers following an earthquake or volcanic eruption. These waves are crucial in understanding Earth's interior and the dynamics of quakes.

Three primary seismic waves exist: P-waves, S-waves, and surface waves. P-waves compress rock, S-waves shear it, and surface waves ripple along Earth's crust, each with unique properties and effects.

P-waves, or Primary waves, are the fastest seismic waves and the first to be detected by seismographs. They can travel through solids, liquids, and gases, compressing and expanding material as they move.

Following P-waves, S-waves, or Secondary waves, travel slower and solely through solid materials. Their sideways or up-and-down motion can cause intense damage during quakes but cannot penetrate Earth's liquid core.

Surface waves travel along Earth's exterior, causing the most destruction due to their high amplitude and longer duration. There are two types: Love waves and Rayleigh waves, each moving the ground distinctly.

P-waves and S-waves are body waves, traveling through Earth's interior, while surface waves are confined to the crust. Body waves help us understand Earth's inner layers, whereas surface waves are key in assessing earthquake damage potential.

The behavior of P-waves and S-waves gives us clues about Earth's core. S-waves' inability to travel through the outer core supports the theory that it is liquid, while P-waves' refraction suggests a solid inner core.

Certain animals, like elephants and cats, can sense seismic waves before humans, often acting erratically before an earthquake strikes.