The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 04, 2001
Filed:
Nov. 05, 1998
Krishnamurthy Ganesan, Sugar Land, TX (US);
Steven F. Crary, Sugar Land, TX (US);
Ralf Heidler, Stafford, TX (US);
Bruno Luong, Stafford, TX (US);
Peter Speier, Stafford, TX (US);
Schlumberger Technology Corporation, Houston, TX (US);
Abstract
The present invention relates generally to an apparatus and method for obtaining an azimuthally resolved nuclear magnetic resonance measurement of an earth formation traversed by a borehole. The measurement can be made while drilling or using a wireline tool. At least one gradient coil is positioned circumferentially around the tool. A magnetic field is produced by the coil in a region of the formation facing the coil. The magnetic field is substantially parallel to the static magnetic field produced by a pair of permanent magnets which form a part of the tool. The additional field causes an additional phase shift for spins located in the region so that the spins subjected to the additional field do not form a spin-echo.