Interpretation of Lg

Lg waves are shown to be identified with higher mode Love wave propagation. The complete demonstration shows that the observations of Lg can be explained only by taking into account the anelasticity of the crust-mantle system, the selective frequency response of the seismograph, and above all, the complicated features of the propagation of Love waves for a number of higher modes, including the relative spectral excitations of these modes. It is not necessary to introduce crustal low-velocity channels to explain the character of the Lg seismogram.