Formation measurements using nonlinear guided waves
AssigneeBaker Hughes, A Ge Company, LLC
InventorsEhsan Khajeh, Yang Liu
Life of this patent
Estimating the term…
Abstract
An embodiment of a method of estimating a property of an earth formation includes: disposing an acoustic tool in a borehole in an earth formation, the acoustic tool including an acoustic source and at least one acoustic receiver; transmitting acoustic signals into the borehole by the acoustic source, the acoustic signals having at least one linear guided wave mode that propagates along a surface of the borehole; receiving the acoustic signals by at least one receiver; analyzing, by a processor, the acoustic signals to measure non-linear harmonic waves generated by the formation is response to the at least one linear guided wave mode; and estimating a property of the formation based on the measured non-linear harmonic waves.
Claims20
A method of estimating a property of an earth formation, comprising:
- disposing an acoustic tool in a borehole in an earth formation, the acoustic tool including an acoustic source and at least one acoustic receiver;
- selecting a linear guided wave mode having a mode and frequency that are configured to induce non-linear harmonic guided waves that propagate along the borehole, the mode and the frequency selected based on dispersion characteristics of the formations;
- transmitting acoustic signals into the borehole by the acoustic source, the acoustic signals having the linear guided wave mode that propagates along a surface of the borehole;
- receiving the acoustic signals by at least one receiver, the acoustic signals including a harmonic of the linear guided wave mode, the harmonic generated by the formation in response to the linear guided wave mode and propagating along the borehole as the non-linear harmonic guided waves;
- analyzing, by a processor, the acoustic signals to measure the non-linear harmonic guided waves;
- and
- estimating a property of the formation based on the measured non-linear harmonic waves.
A system for estimating a property of an earth formation, comprising:
- an acoustic tool configured to be disposed in a borehole in an earth formation, the acoustic tool including an acoustic source configured to generate a linear guided wave mode that propagates along a surface of the borehole, the linear guided wave mode having a mode and frequency selected to induce non-linear harmonic guided waves that propagate along the borehole, the mode and the frequency selected based on dispersion characteristics of the formation;
- a receiver configured to receive acoustic signals including a harmonic of the linear guided wave mode, the harmonic generated by the formation in response to the linear guided wave mode and propagating along the borehole as the non-linear harmonic guided waves;
- and
- a processor configured to analyze acoustic signals received at the acoustic receiver, measure the non-linear harmonic guided waves, and estimate a property of the formation based on the measured non-linear harmonic waves.
Dependencies are inferred from the claim text.