Elements of Seismic Dispersion

This is a recording of the 2012 Distinguished Instructor Short Course (DISC) by Christopher L. Liner. The classical meaning of the word dispersion is frequency-dependent velocity. Here we take a more general definition that includes not only wave speed but also interference, attenuation, anisotropy, reflection characteristics, and other aspects of seismic waves that show frequency dependence. At first impression, the topic seems self-evident: of course everything is frequency dependent. Much of classical seismology and wave theory is nondispersive: the theory of P- and S-waves, Rayleigh waves in a half-space, geometric spreading, reflection and transmission coefficients, head waves, and so forth. Yet when we look at real data, strong dispersion abounds. This course is a survey of selected frequency-dependent phenomena that routinely are encountered in reflection-seismic data. Catalog #235A is the accompanying DISC book.