Determining a full electromagnetic coupling tensor using multiple antennas
US10768333B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 15, 2016 |
| Grant date | Sep 8, 2020 |
| Priority date | — |
| Expiry date | Aug 18, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A downhole electromagnetic logging tool having two or more antenna groups spaced along a longitudinal axis of the logging tool, each antenna group having one antenna or multiple antennas proximally located or collocated, each antenna group having at least one tilted antenna, at least one antenna group having, in addition to the tilted antenna, at least one transverse or axial antenna, and any given pair of antenna groups comprising at least four antennas is disclosed. The logging tool is disposed in a wellbore penetrating a formation and, while rotating, measures a tool rotation angle, transmits an electromagnetic signal from one antenna group, and receives the electromagnetic signal with another antenna group. Elements of an electromagnetic coupling tensor are determined using the received electromagnetic signal and the measured tool rotation angle, and properties of the formation using one or more elements of the determined electromagnetic coupling tensor are inferred.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.