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For guided wave propagation in boreholes, perturbation theory is used to calculate (1) the partial derivative of the wavenumber or frequency with respect to an elastic modulus or density, (2) group velocity, and (3) the ...

Phase velocity and attenuation of guided waves have been estimated from multireceiver, full waveform, acoustic logging data using the extended Prony's method. Since a formation affects velocity and attenuation, estimating ...

The Lagrangian for guided waves in a completely general borehole model is presented. Rayleigh's principle is used to derive the first order perturbations in wavenumber and frequency due to slight perturbations in the ...

Phase velocity and attenuation of guided waves have been estimated from acoustic logging data recorded by a receiving array. The method uses data from multiple sources and successive depths yielding more accurate estimates ...

Using acoustic logging data, we develop a method of estimating the horizontal shear modulus C[subscript 66]) of a transversely isotropic formation with its axis of symmetry parallel to that of the borehole. The data for ...

A method of calculating dispersion curves for guided waves in slight, azimuthally anisotropic formations is developed with perturbation theory. The fluid is assumed to be inviscid, the formation perfectly elastic and ...

We have studied the velocity dispersion of guided waves in transversely isotropic formations. Theoretical velocity dispersion curves were calculated with elastic constants based on laboratory and field measurements and ...