maanjäristysaaltoina

Maanjäristysaaltoina, also known as seismic waves, are vibrations that travel through the Earth’s layers as a result of earthquakes, volcanic eruptions, or other explosions. These waves are the primary source of information about the Earth's interior.

There are two main types of seismic waves: body waves and surface waves. Body waves travel through the Earth's interior. The most common body waves are P-waves (primary waves) and S-waves (secondary waves). P-waves are compressional waves, meaning they move particles in the same direction as the wave is traveling. They are the fastest seismic waves and can travel through solids, liquids, and gases. S-waves are shear waves, meaning they move particles perpendicular to the direction of wave travel. They are slower than P-waves and can only travel through solids.

Surface waves travel along the Earth's surface. They are generated when body waves reach the surface. The two main types of surface waves are Love waves and Rayleigh waves. Love waves move the ground horizontally, perpendicular to the direction of travel. Rayleigh waves create a rolling motion, similar to ocean waves, with particles moving in an elliptical path. Surface waves are typically slower than body waves but often cause more damage during an earthquake because their amplitude is larger.

The study of seismic waves, seismology, allows scientists to understand earthquake mechanisms, locate epicenters, and map the Earth's internal structure, including the crust, mantle, and core. The travel times and characteristics of these waves provide crucial data for geophysical research.