Methods and systems for determining formation parameters using a rotating tool equipped with tilted antenna loops

Patent metadata

Field	Value
Publication number	US-9753175-B2
Application number	US-201514591540-A
Country	US
Kind code	B2
Filing date	Jan 7, 2015
Priority date	May 5, 2011
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

Methods and systems for characterizing a formation are disclosed. A tool is placed in the formation. The tool comprises a perpendicular antenna set and a parallel antenna set. The perpendicular antenna set comprises at least one transmitter antenna oriented perpendicular to at least one receiver antenna and the parallel antenna set comprises at least one transmitter antenna oriented parallel to at least one receiver antenna. Data is obtained from the tool and used to determine a compensated geosignal for each of the perpendicular antenna set and the parallel antenna set. The determined compensated geosignal is used to characterize the formation.

First claim

What is claimed is:

1. A method for characterizing a formation comprising:
placing a tool in the formation;
wherein the tool comprises a perpendicular antenna set and a parallel antenna set;
wherein the perpendicular antenna set comprises at least one first transmitter antenna oriented perpendicular to at least one first receiver antenna and the parallel antenna set comprises at least one second transmitter antenna oriented parallel to at least one second receiver antenna;

obtaining first data from the at least one first receiver antenna and second data from the at least one second receiver antenna;
using the first data to determine a first compensated geosignal for the perpendicular antenna set and the second data to determine a second compensated geosignal for the parallel antenna set, the first compensated geosignal and the second compensated geosignal corresponding to a first formation characteristic;
determining the first formation characteristic based, at least in part, on a comparison of the first compensated geosignal and the second compensated geosignal, wherein
the first formation characteristic is at least one of an anisotropy of the formation, a relative dip of the formation, a relative strike of the formation, a boundary of the formation and a distance to the boundary of the formation.

2. A method for characterizing a formation comprising:
placing a tool in the formation;
wherein the tool comprises a perpendicular antenna set, a parallel antenna set, and a rotational position sensor;
wherein the perpendicular antenna set comprises at least one first transmitter antenna oriented perpendicular to at least one first receiver antenna and the parallel antenna set comprises at least one second transmitter antenna oriented parallel to at least one second receiver antenna;

obtaining first data from the at least one first receiver antenna and second data from the at least one second receiver antenna;
using the first data to determine a first compensated geosignal for the perpendicular antenna set and the second data to determine a second compensated geosignal for the parallel antenna set, the first compensated geosignal and the second compensated geosignal corresponding to a first formation characteristic;
determining the first formation characteristic by comparing the first compensated geosignal and the second compensated geosignal.

3. The method of claim 2 , wherein:
the first formation characteristic is at least one of an anisotropy of the formation, a relative dip of the formation, a relative strike of the formation, a boundary of the formation and a distance to the boundary of the formation.

4. A method for characterizing a formation comprising:
placing a tool in the formation;
wherein the tool comprises a perpendicular antenna set and a parallel antenna set;
wherein the perpendicular antenna set comprises at least one first transmitter antenna oriented perpendicular to at least one first receiver antenna and the parallel antenna set comprises at least one second transmitter antenna oriented parallel to at least one second receiver antenna;

obtaining a first data set comprising a first compensated geosignal and a second compensated geosignal corresponding to a first formation characteristic,
wherein obtaining the first data set further comprises:
obtaining first data from the at least one first receiver antenna and second data from the at least one second receiver antenna;
using the first data to determine the first compensated geosignal for the perpendicular antenna set and the second data to determine the second compensated geosignal for the parallel antenna set;

rotating the electromagnetic resistivity logging tool;
obtaining a second data set comprising a third compensated geosignal and a fourth compensated geosignal corresponding to the first formation characteristic,
wherein obtaining the second data set further comprises
obtaining third data from the at least one first receiver antenna and fourth data from the at least one second receiver antenna;
using the third data to determine the third compensated geosignal and the fourth data to determine the fourth compensated geosignal;

determining the first formation characteristic based, at least in part, on a comparison of the first data set and the second data set.

5. The method of claim 4 , wherein:
the first formation characteristic is at least one of an anisotropy of the formation, a relative dip of the formation, a relative strike of the formation, a boundary of the formation and a distance to the boundary of the formation.

6. The method of claim 4 , wherein:
the tool further comprises a rotational position sensor.

7. The method of claim 6 , further comprising obtaining, from the rotational position sensor, one or more measurements, wherein the one or more measurements comprise at least one or more of a tool face angle, an inclination angle, and an azimuth orientation angle of a borehole of the formation.

8. The method of claim 7 , further comprising:
determining a coupling matrix using the at least one or more measurements, the first compensated geosignal and the second compensated geosignal; and
geosteering the borehole based on the coupling matrix.

9. The method of claim 4 , further comprising measuring one or more orientation measurements of a borehole of the formation using at least one of a magnetometer, an accelerometer and a gyroscope.

10. The method of claim 4 , wherein determining the first formation characteristic comprises identifying an isotropic formation, and wherein identifying the isotropic formation comprises determining that the first compensated geosignal and the second compensated geosignal are below a minimum threshold value.

11. The method of claim 4 , wherein determining the first formation characteristic comprises identifying an anisotropic formation, and wherein identifying an anisotropic formation comprises determining that the second compensated geosignal exceeds the minimum threshold value and the first compensated geosignal is less than the minimum threshold value.

12. The method of claim 4 , wherein determining the first formation characteristic comprises identifying a tool boundary, and wherein identifying the tool around boundary comprises determining that both the first compensated geosignal and the second compensated geosignal exceed the minimum threshold value.

13. The method of claim 4 , wherein determining the first formation characteristic comprises identifying a tool across boundary, and wherein identifying the tool across boundary comprises determining that the first compensated geosignal at least one of changes from a positive value to a negative value and changes from a negative value to a positive value.

14. The method of claim 2 , further comprising obtaining, from the rotational position sensor, one or more measurements, wherein the one or more measurements comprise at least one or more of a tool face angle, an inclination angle, and an azimuth orientation angle of a borehole of the formation.

15. The method of claim 14 , further comprising:
determining a coupling matrix using the at least one or more measurements, the first compensated geosignal and the second compensated geosignal; and
geosteering the borehole based on the coupling matrix.

16. The method of claim 1 , further comprising measuring one or more orientation measurements of a borehole of the formation using at least one of a magnetometer, an accelerometer and a gyroscope.

17. The method of claim 1 , wherein determining the first formation characteristic co

Assignees

• Halliburton Energy Services Inc
• Haliburton Energy Services Inc

Inventors

• Li Shanjun
• Wu Hsu-Hsiang
• Bittar Michael

Classifications

• G01V3/28 Primary

  using induction coils · CPC title

• G01V3/30 Primary

  operating with electromagnetic waves · CPC title