Patent ID: 6522974
Filing Date: 2003-02-18
Classification: G01V,G08B

Abstract:
A method of seismic prospecting using a vibratory source, the method comprising:(a) activating the vibratory source using a reference pilot signal, said reference pilot signal having an initial frequency at a starting time and an ending frequency at an ending time; (b) determining an instantaneous phase of the reference pilot signal; (c) measuring the outgoing or near-field signal from said vibratory source; (d) defining a plurality of basis signals based on sinusoids of multiples of the instantaneous phase of the reference pilot signal, each of said basis signals being a sinusoid having a linear instantaneous frequency and instantaneous differential phase wherein said linear instantaneous frequency is a multiple of an instantaneous frequency of the reference pilot signal; and (e) representing said measured outgoing or near-field signal as a sum of the basis signals weighted by associated instantaneous amplitudes, each associated with a harmonic of the outgoing or near field signal.