Methodology for interpretation and analysis of NMR distributions
US7804297B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 30, 2008 |
| Grant date | Sep 28, 2010 |
| Priority date | — |
| Expiry date | Feb 20, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/50
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Pulse sequences are applied to a fluid in an earth formation in a static magnetic field and NMR spin echo signals are obtained. The signals are inverted to give T2 distributions at a plurality of depths. Similarities between logs of the T2 bins with resistivity and/or gamma ray logs are used to identify and subtract contributions to the NMR signal from oil. having internal gradients. From the received signals, relaxation and diffusion characteristics of the fluid are determined. The determination takes into account the internal field gradients. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.