Hello, I'm an expert in seismology with a focus on understanding the different types of seismic waves and their impacts on human structures and the natural environment. The L wave of an earthquake is actually a term that is not commonly used in the scientific community. However, it seems to be referring to a type of surface wave, which is one of the two main categories of earthquake waves, the other being body waves. Surface waves are slower than body waves and travel along the Earth's surface. There are two main types of surface waves: Love waves (L-waves) and Rayleigh waves (R-waves). Love waves, which might be what you're referring to when you mention L waves, are transverse waves that move the ground from side to side in a horizontal motion. They are named after the English engineer Augustus Edward Hough Love who first described them. Love waves do not displace the ground in the vertical direction and are particularly damaging because they cause strong horizontal shaking that can be very destructive to buildings and infrastructure. On the other hand, Rayleigh waves cause both vertical and horizontal ground motion and are known for their elliptical particle motion. They are often the waves that cause the most damage during an earthquake because they have lower frequencies and higher amplitudes, which can lead to more intense shaking and greater potential for damage. read more >>

Surface waves, the slowest earthquake waves, travel along the surface of the earth rather than down into the earth. Although they are the slowest of all earthquake waves, L waves usually cause more damage to society than P or S waves.read more >>