Back to results
US 6,586,932 B1Granted
Enhanced performance antennas for NMR logging
AssigneeSchlumberger Technology Corporation
InventorsReza Taherian, Richard P. Harris
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeSchlumberger Technology Corporation
InventorsReza Taherian, Richard P. Harris
Estimating the term…
An antenna design for a downhole nuclear magnetic resonance logging tool is enhanced to shape the resultant RF field generated by the antenna. The enhancement is accomplished by adding additional turns to a portion of the antenna, either circumscribing a ferrite material or located on the surface of an at least partially non-conductive material. The additional turns or half turns in combination with the RF field from parallel antenna portions result in a RF field contribution that is proportionally higher than the RF field contribution from the coil portions which are not enhanced. Further, the total RF field can be shaped over a earth sample region depending on placement of the enhancing turns. In this way, for example, the total RF field can be generated to achieve an orthogonal alignment with a static magnetic field over a larger region of the sample.
An NMR antenna apparatus, comprising:
A method of producing from an antenna coil a total RF field in a sample of earth formation, the method comprising the steps of:
A method generating a total RF field from an antenna coil in a sample of an earth formation, comprising the steps of:
An NMR measurement apparatus, comprising:
Dependencies are inferred from the claim text.