Conductive pad around electrodes for investigating the wall of a borehole in a geological formation
US6891377B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2001 |
| Grant date | May 10, 2005 |
| Priority date | — |
| Expiry date | Mar 29, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention relates to apparatus for a tool for investigating the wall of a borehole in a geological formation, the apparatus comprising: a non-conductive pad having an inside face and an outside face for pressing against the wall; a set of measurement electrodes mounted on the outside face of the pad and means for measuring the potential difference between two measurement electrodes; and both a source electrode adapted to inject current into the geological formation and a return electrode, the set of measurement electrodes being situated between the source electrode and the return electrode for the current; the apparatus being characterized in that the pad comprises an electrically conductive portion covering the entire measurement electrode zone and electrically insulated from the measurement electrodes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.