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.
|Original language||English (US)|
|Number of pages||11|
|Journal||Geophysical Journal International|
|State||Published - Apr 1993|
All Science Journal Classification (ASJC) codes
- Geochemistry and Petrology
- Berry phase
- JWKB theory
- surface waves.