Method and apparatus for measuring formation conductivities from within cased wellbores by combined measurement of casing current leakage and electromagnetic response
US7272503B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 2006 |
| Grant date | Sep 18, 2007 |
| Priority date | — |
| Expiry date | Oct 26, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for determining spatial distribution of resistivity of Earth formations surrounding a wellbore having a conductive pipe therein includes measuring resistivity of the Earth formations using measurements of current leakage along the pipe at selected axial positions. Electromagnetic properties of the Earth formations are measured from within the pipe. The measurements of electromagnetic properties correspond to a larger axial distance and to a greater lateral distance than the measurements of resistivity from current leakage. The current leakage and electromagnetic measurements are jointly inverted to obtain a model of the spatial distribution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.