Surface Waves in Media with Weak Lateral Inhomogeneity

摘要: Surface wave propagation in a vertically varying half-space was treated the preceding chapter by evaluating leading term exact integral solution of equations motion, which describes surface field far from source (see (1.27), (1.32), (1.33)). Exact formulas for structure with both vertical and lateral variation cannot be derived, so above approach to analysis waves is inapplicable. An arbitrary inhomogeneity can handled only numerical methods. Nevertheless, when much smaller than vertical, procedure similar ray method used construct an approximate corresponding (Woodhouse, 1974; Babich Chikhachev, 1975; et al., 1976; Grigoryeva, 1980). Similarly (Alekseev 1961; Buldyrev, 1972), expanded powers small parameter (this inverse frequency ω describing weak inhomoeeneitv our case).