# US 2015/0177412 A1 · Calibration method for multi-component induction tools > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2015/0177412 A1 - Document ID: US20150177412A1 - Status: Published application - Kind: A1 - Application number: 14/415,675 - Filed: 2014-03-25 - Published: 2015-06-25 - Earliest claimed: 2013-03-28 - Assignees: Haliburton Energy Services, Inc. - Applicants: Halliburton Energy Services, Inc. - Inventors: Luis E. San Martin; Dagang Wu; Baris Guner - Web page: https://patentgrep.com/patent/US20150177412A1 ## CPC - G01V 13/00: Manufacturing, calibrating, cleaning, or repairing instruments or devices covered by groups G01V1/00 – G01V11/00 - G01V 3/104: {using several coupled or uncoupled coils (G01V3/101 takes precedence)} - G01V 3/28: using induction coils - G01V 3/38: Processing data, e.g. for analysis, for interpretation, for correction - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) ## Abstract Calibration tools and procedures that provide one or more calibration methods for multi-component induction tools can include use of a tilted elliptical loop and a circular loop. Measurement signals may be used for analytic calibration of a multicomponent induction tool. Additional apparatus, systems, and methods are disclosed. ## Claims ### Claim 1 A method comprising: generating calibration gain factors of selected coupling components of a multi-component induction tool from measurements using a tilted elliptical loop for analytic calibration of the multi-component induction tool. ### Claim 2 (depends on 1) The method of claim 1, further comprising: generating calibration gain factors of a number of components by using selected gain factors generated from using the tilted elliptical loop. ### Claim 3 (depends on 1) The method of claim 1, further comprising: generating the calibration gain factors of the selected coupling components by generating calibration gain factors of XX, XZ, YY, YZ, ZX, and ZY coupling components of the multi-component induction tool, the multi-component induction tool having a longitudinal axis along a z-axis; generating a calibration gain factor of a ZZ component using a circular loop for the analytic calibration; and generating calibration gain factors of XY and YX coupling components using selected gain factors generated from using the tilted elliptical loop and the circular loop. ### Claim 4 (depends on 3) The method of claim 3, wherein generating the calibration gain factors using the tilted elliptical loop includes: generating signals with the tilted elliptical loop around the multi-component induction tool; generating signals without using the tilted elliptical loop; and generating each respective gain factor of a coupling component based on a difference between a signal correlated to the respective coupling component with the tilted elliptical loop around the multi-component induction tool and a signal correlated to the respective coupling component without using the tilted elliptical loop. ### Claim 5 (depends on 4) The method of claim 4, further comprising: generating the signals with the tilted elliptical loop around the multi-component induction tool at a temperature and with the multi-component induction tool at a height that is the same as when generating the signals without using the tilted elliptical loop. ### Claim 6 (depends on 3) The method of claim 3, further comprising: generating maximum values provided by the tilted elliptical loop by loop sweeping the tilted elliptical loop. ### Claim 7 (depends on 6) The method of claim 6, wherein the loop sweeping is conducted by rotating the multi-component induction tool. ### Claim 8 (depends on 6) The method of claim 6, wherein the loop sweeping is conducted by rotating the tilted elliptical loop. ### Claim 9 (depends on 3) The method of claim 3, further comprising: positioning the tilted elliptical loop at a maximum response of each component along the z-axis and rotating the tilted elliptical loop around the z-axis to capture the maximum. ### Claim 10 (depends on 3) The method of claim 3, further comprising: determining a conductivity offset by measuring a signal with the multi-component induction tool at a height greater than that at which the multi-component induction tool is disposed to generate the calibration gain factors. ### Claim 11 (depends on 3) The method of claim 3, further comprising: determining a sonde error including evaluating temperature effect on the sonde error by characterizing tool response behavior of the multi-component induction tool through heating tests. ### Claim 12 (depends on 3) The method of claim 3, further comprising: calculating earth ground conductivity using only the ZZ component from the multi-component induction tool. ### Claim 13 (depends on 3) The method of claim 3, further comprising: computing ground effects on all components from a forward modeling program or a pre-computed table. ### Claim 14 A machine-readable storage device having instructions stored thereon, which, when performed by a machine, cause the machine to perform operations, the operations comprising: generating calibration gain factors of selected coupling components of a multi-component induction tool from measurements using a tilted elliptical loop for analytic calibration of the multi-component induction tool. ### Claim 15 A system comprising: a multi-component induction tool having an axis; an elliptical loop capable of being positioned around the multi-component induction tool, moveable along the axis, and tiltable with respect to the axis; a processor unit; and a memory unit operatively coupled to the processor unit, the memory unit having instructions stored thereon, which, when executed by the processor unit, cause the system to perform operations, the operations comprising generating calibration gain factors of selected coupling components of the multi-component induction tool from measurements from use of the elliptical loop tilted around the multi-component induction tool to perform analytic calibration of the multi-component induction tool. ### Claim 16 (depends on 15) The system of claim 15, wherein the instructions further comprise: instructions to generate calibration gain factors of a number of components by use of selected gain factors generated from use of the tilted elliptical loop. ### Claim 17 (depends on 15) The system of claim 15, wherein the instructions further comprise instructions to: generate the calibration gain factors of the selected coupling components by generation of calibration gain factors of XX, XZ, YY, YZ, ZX, and ZY coupling components of the multi-component induction tool, the axis being along a z-axis; generate a calibration gain factor of a ZZ component from use of a circular loop for the analytic calibration; and generate calibration gain factors of XY and YX coupling components from use of selected gain factors generated from use of the tilted elliptical loop and the circular loop. ### Claim 18 (depends on 17) The system of claim 17, wherein instructions to generate the calibration gain factors from use of the tilted elliptical loop includes instructions to: generate signals with the tilted elliptical loop around the multi-component induction tool; generate signals without use of the tilted elliptical loop; and generate each respective gain factor of a coupling component based on a difference between a signal correlated to the respective coupling component with the tilted elliptical loop around the multi-component induction tool and a signal correlated to the respective coupling component without use of the tilted elliptical loop. ### Claim 19 (depends on 18) The system of claim 18, wherein the instructions further comprise: instructions to generate the signals with the tilted elliptical loop around the multi-component induction tool at a temperature and with the multi-component induction tool at a height that is the same as when generating the signals without use of the tilted elliptical loop. ### Claim 20 (depends on 17) The system of claim 17, wherein the instructions further comprise: instructions to generate maximum values provided by the tilted elliptical loop by a loop sweep of the tilted elliptical loop. ### Claim 21 (depends on 20) The system of claim 20, wherein the loop sweep includes rotation of the multi-component induction tool. ### Claim 22 (depends on 20) The system of claim 20, wherein the loop sweep includes rotation of the tilted elliptical loop. ### Claim 23 (depends on 17) The system of claim 17, wherein the instructions further comprise: instructions to position the tilted elliptical loop at a maximum response of each component along the z-axis and to rotate the tilted elliptical loop around the z-axis to capture the maximum. ### Claim 24 (depends on 17) The system of claim 17, wherein the instructions further comprise: instructions to determine a conductivity offset by measurement of a signal with the multi-component induction tool at a height greater than that at which the multi-component induction tool is disposed to generate the calibration gain factors. ### Claim 25 (depends on 17) The system of claim 17, wherein the instructions further comprise: instructions to determine a sonde error including evaluation of temperature effect on the sonde error by characterization of tool response behavior of the multi-component induction tool through heating tests. ### Claim 26 (depends on 17) The system of claim 17, wherein the instructions further comprise: instructions to calculate earth ground conductivity by use of only the ZZ component from the multi-component induction tool. ### Claim 27 (depends on 17) The system of claim 17, wherein the instructions further comprise: instructions to compute ground effects on all components from a forward modeling program or a pre-computed table. ### Claim 28 (depends on 14) The machine-readable storage device of claim 14, the operations further comprising: generating the calibration gain factors of the selected coupling components by generating calibration gain factors of XX, XZ, YY, YZ, ZX, and ZY coupling components of the multi-component induction tool, the multi-component induction tool having a longitudinal axis along a z-axis; generating a calibration gain factor of a ZZ component using a circular loop for the analytic calibration; and generating calibration gain factors of XY and YX coupling components using selected gain factors generated from using the tilted elliptical loop and the circular loop.