公开(公告)号：US20170357025A1

公开(公告)日：2017-12-14

申请号：US15494009

申请日：2017-04-21

Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION

Inventor： MARTIN D. HÜRLIMANN ,  SOUMYAJIT MANDAL ,  VAN MAI DO ,  YI-QIAO SONG

IPC: G01V3/32 ,  G01R33/561 ,  G01N24/08 ,  G01R33/44 ,  G01R33/38

CPC classification number: G01V3/32 ,  G01N24/081 ,  G01R33/3808 ,  G01R33/445 ,  G01R33/5617

Abstract: Illustrative embodiments are directed to applying a nuclear magnetic resonance sequence to a substance within an inhomogeneous static magnetic field. Various embodiments include applying a series of refocusing pulses to the substance, each refocusing pulse in the series of refocusing pulses having at least two segments, and a total pulse duration less than or equal to approximately 1.414 times T180. Various embodiments can further include applying an excitation pulse to the substance in the inhomogeneous static magnetic field, where the excitation pulse generates an initial magnetization that is aligned with a refocusing axis produced by a refocusing cycle that is performed after the excitation pulse.