Title:
DETERMINING THE LARMOR FREQUENCY FOR NMR TOOLS
Document Type and Number:
WIPO Patent Application WO/2011/119528
Kind Code:
A3
Abstract:
The Larmor frequency for an in situ nuclear magnetic resonance (NMR) tool is determined and used to acquire NMR data. An NMR tool is provided and placed in situ, for example, in a wellbore. An initial estimate of the Larmor frequency for the in situ NMR tool is made and NMR data are acquired using the in situ NMR tool. A spectral analysis is performed on the NMR data, or optionally, the NMR data are digitized and a discrete Fourier transform (DFT) is performed on the digitized NMR data. The modal frequency of the spectral analysis or DFT is determined, and the Larmor frequency for the in situ NMR tool is determined using the modal frequency. The NMR tool is modified to transmit at the determined Larmor frequency and then used to acquire further NMR data.
Inventors:
ANAND VIVEK (US)
FREEDMAN ROBERT (US)
DEMENTYEV ANATOLY (US)
TABRIZI PAYAM (US)
CATINA DANIEL (US)
FREEDMAN ROBERT (US)
DEMENTYEV ANATOLY (US)
TABRIZI PAYAM (US)
CATINA DANIEL (US)
Application Number:
PCT/US2011/029311
Publication Date:
February 16, 2012
Filing Date:
March 22, 2011
Export Citation:
Assignee:
SCHLUMBERGER CA LTD (CA)
SCHLUMBERGER TECHNOLOGY BV (NL)
PRAD RES & DEV LTD
SCHLUMBERGER SERVICES PETROL (FR)
SCHLUMBERGER HOLDINGS
ANAND VIVEK (US)
FREEDMAN ROBERT (US)
DEMENTYEV ANATOLY (US)
TABRIZI PAYAM (US)
CATINA DANIEL (US)
SCHLUMBERGER TECHNOLOGY BV (NL)
PRAD RES & DEV LTD
SCHLUMBERGER SERVICES PETROL (FR)
SCHLUMBERGER HOLDINGS
ANAND VIVEK (US)
FREEDMAN ROBERT (US)
DEMENTYEV ANATOLY (US)
TABRIZI PAYAM (US)
CATINA DANIEL (US)
International Classes:
G01V3/32; E21B47/00; G01V3/34
Foreign References:
| US5451873A | 1995-09-19 | |||
| US7026814B2 | 2006-04-11 | |||
| US7215119B2 | 2007-05-08 | |||
| US20090116595A1 | 2009-05-07 |
Attorney, Agent or Firm:
FONSECA, Darla et al. (200 Gillingham Lane MD200-9Sugar Land, TX, US)
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