Patent ID: 7330799
Filing Date: 2008-02-12
Classification: G01V

Abstract:
1. A method, using a Rayleigh wave, for establishing a set of dispersion curves characterizing a medium, wherein each dispersion curve is associated to a propagation mode of said Rayleigh wave, the method comprising: deploying on a surface of the medium a plurality of sensors; generating a surface wave in the medium; monitoring with said sensors a propagation of the surface wave for providing a plurality of signals in the time domain, wherein said signals comprise a spectrum of frequencies; determining, from said plurality of signals, and for each of said frequencies, an energy distribution as a function of phase travel time and group travel time, wherein said determining an energy distribution comprises computing a wavelet transform of said signals as a function of said phase travel time and group travel time for providing said energy distribution; identifying a set of said propagation modes of the Rayleigh wave using said energy distribution; establishing, for each identified propagation mode, a dispersion curve using said energy distribution, thereby providing said set of dispersion curves characterizing said medium; and further comprising at least one of: