Focusing on recent developments in the area of seismic wave propagation and scattering, this text combines information from numerous sources to present a coherent introduction to the theory of scattering in acoustic and elastic materials. With the emphasis firmly on the lithosphere, the book includes analyses of observations using the theoretical methods developed. Written for advanced undergraduates and beginning graduates of geophysics and planetary sciences, this is also of interest to civil engineers, seismologists, acoustical engineers, and others interested in wave propagation through inhomogeneous elastic media.

Résumé

Seismic waves generated both by natural earthquakes and by man-made sources have produced an enormous amount of information about the Earth's interior. In classical seismology, the Earth is modeled as a sequence of uniform horizontal layers (or sperical shells) having different elastic properties and one determines these properties from travel times and dispersion of seismic waves. The Earth, however, is not made of horizontally uniform layers, and classic seismic methods can take large-scale inhomogeneities into account. Smaller-scale irregularities, on the other hand, require other methods. Observations of continuous wave trains that follow classic direct S waves, known as coda waves, have shown that there are heterogeneities of random size scattered randomly throughout the layers of the classic seismic model. This book focuses on recent developments in the area of seismic wave propagation and scattering through the randomly heterogeneous structure of the Earth, with emphasis on the lithosphere. The presentation combines information from many sources to present a coherent introduction to the theory of scattering in acoustic and elastic materials and includes analyses of observations using the theoretical methods developed.

Contenu
Heterogeneity in the Lithosphere.- Phenomenological Modeling of Coda-Wave Excitation.- Born Approximation for Wave Scattering in Inhomogeneous Media.- Attenuation of High-Frequency Seismic Waves.- Synthesis of Three-Component Seismogram Envelopes for Earthquakes Using Scattering Amplitudes from the Born Approximation.- Envelope Synthesis Based on the Radiative Transfer Theory: Multiple Scattering Models.- Diffraction and Broadening of Seismogram Envelopes.- Summary and Epilogue.