Virtual steering of induction tool for determination of formation dip angle
US6727706B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 2001 |
| Grant date | Apr 27, 2004 |
| Priority date | — |
| Expiry date | Aug 9, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method is disclosed for using a triad induction tool to identify the formation strike and dip angles. The method can be performed in real time. In one embodiment, the method includes: (1) measuring a magnetic coupling between transmitter coils and receiver coils of a tool in the borehole; (2) obtaining from the measured coupling a strike angle between the tool and the formation; (3) applying a rotational transformation to the coupling measurements to correct for the strike angle; and (4) applying a predetermined set of rotational transformations to the coupling to determine coupling term values as a function of rotation angle. A least-squares curve fit or a Hough transform of the derivative of the coupling term values with respect to position may be used to identify the dip angle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.