Electrical imaging in conductive and non-conductive mud
US6957708B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 2003 |
| Grant date | Oct 25, 2005 |
| Priority date | — |
| Expiry date | Mar 31, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/30
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The invention is a method and apparatus for determining an electrical property a formation surrounding a borehole with a measuring-while-drilling device. The apparatus an antenna configuration disposed along the outer face of an extendable stabilizer joined to a rotatable drill collar. Typically, two receivers and two transmitters are spaced along the longitudinal axis of the drill collar, with the two receivers spaced symmetrically in between the two transmitters. Alternatively, receivers and transmitters can be spaced along the circumference, possibly over multiple stabilizers. Multiple assemblies can be used. Data can be obtained with the transmitter-receiver assembly held in a stationary position or rotating circumferentially. Apparatus can be operated in a “broadside” configuration, an “endfire” configuration, or a configuration in which transmitter coils and receiver coils are oriented orthogonally to each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.