Back to results
US 2022/0373707 A1Published application
A data driven method to invert for the formation anisotropic constants using borehole sonic data
AssigneeSchlumberger Technology Corporation
InventorsTing Lei, Romain Prioul
Life of this patent
Estimating the term…
Abstract
A method is presented wherein inversion for formation anisotropic constants is achieved using borehole sonic data.
Claims14
A method, comprising:
- obtaining a waveform;
- processing the obtained waveform to obtain at least one of a Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersion;
- at least one of performing a computation and obtaining a library computation for interpolated theoretical dispersions of the Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersions;
- performing an initial estimate of mud slowness using both the processing of the obtained waveform and the interpolating the theoretical dispersions;
- calculating a mismatch between the processed waveform obtaining the at least one Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersion and the theoretical dispersions of the Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersions;
- estimating at least one DTmud value as a vertical depth profile;
- calculating a second mismatch between the theoretical dispersion and the processed waveform using the at least one estimated DTmud value;
- estimating at least one parameter by minimizing the second mismatch;
- using regression, calculating the at least one parameter over multiple depths;
- updating values for the at least one parameter based upon the regression;
- calculating a third mismatch between the theoretical and measured dispersions based upon the updated values for the at least one parameter based upon the regression;
- and
- estimating a final value of the at least one parameter by minimizing a mismatch between the theoretical and measured dispersions.
10 more elements
A method, comprising:
- obtaining a waveform from a sonic borehole device in a formation;
- processing the obtained waveform from the sonic borehole device to obtain at least one value of a Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersion;
- performing a computation to produce a theoretical dispersion of the Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersions for the waveform;
- performing an initial estimate of mud slowness using both the processing of the obtained waveform and the theoretical dispersion;
- calculating a first mismatch between the processed waveform obtaining the at least one Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersions and the theoretical dispersions of the Stoneley, flexural, quadrupole and Pseudo-Rayleigh dispersions;
- estimating at least one DTmud value as a vertical depth profile;
- calculating a second mismatch between the theoretical dispersion and the processed waveform using the at least one estimated DTmud value;
- estimating at least one Thomson parameter for the formation by minimizing the second mismatch;
- using regression, calculating at least one revised Thomson parameter over multiple depths;
- calculating a third mismatch between the theoretical and measured dispersions based upon the updated values for Thomson parameter based upon the regression;
- and
- estimating a final value of the at least one Thomson parameter by minimizing a mismatch between the theoretical and measured dispersions.
9 more elements
Dependencies are inferred from the claim text.