P-wave anisotropy determination using borehole measurements
AssigneeBaker Hughes Incorporated
InventorsVladimir Dubinsky, Xiao Ming Tang, Yibing Zheng, Douglas J. Patterson
Life of this patent
Estimating the term…
Abstract
A phased array of transducers is used to generate elastic waves into the earth formation in a selected direction. The impedance measured at the input to the transducer array is indicative of the elastic impedance of the earth formation in the selected direction.
Claims21
A method of estimating a value of an impedance of a transversely isotropic earth formation, the method comprising:
- conveying a logging tool into a borehole in the earth formation;
- activating at least one transducer on the logging tool in contact with a wall of the borehole for generating an elastic wave into the earth formation at a selected angle inclined to a longitudinal axis of the borehole;
- estimating the value of the impedance of the transversely isotropic earth formation at the selected angle using a voltage of the at least one transducer and a current in the at least transducer;
- and
- recording the estimated value of the impedance of the transversely isotropic earth formation at the selected angle on a suitable medium.
An apparatus for determining a value of an impedance of a transversely isotropic earth formation, the apparatus comprising:
- a logging tool configured to be conveyed into a borehole;
- at least one transducer on the logging tool in contact with a wall of the borehole configured to generate an elastic wave into the earth formation at a selected angle inclined to a longitudinal axis of the borehole;
- and
- a processor configured to:
- (A) estimate an impedance of the transversely isotropic earth formation at the selected angle using a voltage of the at least one transducer and a current in the at least one transducer;
- and
- (B) record the estimated impedance of the transversely isotropic earth formation at the selected angle on a suitable medium.
A computer-readable medium accessible to a processor, the computer-readable medium comprising instructions which enable the processor to:
- use an output of at least one transducer on a logging tool in contact with a wall of a borehole configured to generate an elastic wave at a selected angle into a transversely isotropic earth formation;
- estimate an impedance of the transversely isotropic earth formation at the selected angle using a voltage of the at least one transducer and a current in the at least one transducer;
- and
- record the estimated value of the impedance of the transversely isotropic earth formation at the selected angle on a suitable medium.
Dependencies are inferred from the claim text.