Open AccessSurface Wave Propagation In A Slowly Varying Anisotropic Waveguide
Author(s) -
Tromp Jeroen,
Dahlen F. A.
Publication year - 1993
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1993.tb02542.x
Subject(s) - wave vector , adiabatic process , anisotropy , physics , waveguide , wave propagation , dispersion relation , surface wave , eigenfunction , path integral formulation , classical mechanics , condensed matter physics , quantum mechanics , optics , quantum , eigenvalues and eigenvectors
SUMMARY We present a JWKB theory which describes the propagation of seismic surface waves in a laterally heterogeneous, anisotropic waveguide. We introduce a local dispersion relation and local vertical eigenfunctions which depend explicitly on the direction of the local wavevector as a consequence of the anisotropy. the variation of amplitude along a surface wave ray path is determined by a conservation law for the surface wave energy. Apart from the usual dynamical phase, which is the integral of the local wavevector along a ray path, there is an additional variation in phase in a general anisotropic waveguide. This additional phase, which is an analogue of the Berry phase in adiabatic quantum mechanics, vanishes in a waveguide with a local vertical two‐fold symmetry axis or a local horizontal mirror plane.