Wave Fields in Real Media: Wave Propagation in Anisotropic, Anelastic, Porous and Electromagnetic Media examines the differences between an ideal and a real description of wave propagation, starting with the introduction of relevant constitutive relations. The differential formulation can be written in terms of memory variables, and Biot theory is used to describe wave propagation in porous media. For each constitutive relation, a plane-wave analysis is performed to illustrate the physics of wave propagation. New topics are the S-wave amplification function, Fermat principle and its relation to Snell law, bounds and averages of seismic Q, seismic attenuation in partially molten rocks, and more. This book contains a review of the main direct numerical methods for solving the equation of motion in the time and space domains. The emphasis is on geophysical applications for seismic exploration, but researchers in the fields of earthquake seismology, rock acoustics and material science - including many branches of acoustics of fluids and solids - may also find this text useful.