Love wave

Type of surface seismic wave

Diagram illustrating the motion of a Love wave.

Love waves are a type of surface wave that travel along the surface of a solid medium, such as the Earth. They are named after the British mathematician Augustus Edward Hough Love, who first described them mathematically in 1911. Love waves are a form of seismic wave and are characterized by their horizontal motion, which is perpendicular to the direction of wave propagation.

Characteristics

Love waves are distinguished from other types of seismic waves by their unique motion. Unlike P-waves and S-waves, which travel through the Earth's interior, Love waves are confined to the surface. They cause horizontal shearing of the ground, which can be particularly damaging to structures during an earthquake.

The motion of Love waves is transverse to the direction of propagation and occurs in a horizontal plane. This means that the particles of the medium move back and forth in a direction perpendicular to the wave's travel direction. This type of motion is similar to the movement of a snake, which is why Love waves are sometimes referred to as "snake waves."

Formation

Love waves are generated when S-waves interact with the Earth's surface. As S-waves reach the surface, they can be converted into Love waves if the conditions are right. This typically occurs in layered media, where there is a contrast in the elastic properties of the layers. The presence of a low-velocity layer overlying a higher-velocity layer is conducive to the formation of Love waves.

Propagation

Love waves travel at a speed that is slower than P-waves but faster than S-waves. Their velocity depends on the frequency of the wave and the properties of the medium through which they are traveling. The dispersion of Love waves, where different frequencies travel at different speeds, can provide valuable information about the Earth's subsurface structure.

Effects

During an earthquake, Love waves are often responsible for much of the damage to buildings and infrastructure. Their horizontal shearing motion can cause severe shaking, leading to the collapse of structures that are not designed to withstand such forces. The amplitude of Love waves can be particularly large, especially in areas with soft sedimentary layers, which can amplify the wave motion.

Applications

Seismologists study Love waves to gain insights into the Earth's crust and upper mantle. By analyzing the dispersion of Love waves, scientists can infer the properties of the Earth's layers, such as their thickness and elastic moduli. This information is crucial for understanding tectonic processes and assessing seismic hazards.

Related pages

• Seismic wave
• Rayleigh wave
• P-wave
• S-wave
• Earthquake