公开(公告)号：US10001578B2

公开(公告)日：2018-06-19

申请号：US14272325

申请日：2014-05-07

Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION

Inventor： Soumyajit Mandal ,  Van D. M. Koroleva ,  Troy Borneman ,  Martin D. Hürlimann

IPC: G01V3/00 ,  G01V3/14 ,  G01V3/32 ,  G01V3/38

CPC classification number: G01V3/14 ,  G01V3/32 ,  G01V3/38

Abstract: A method for applying a nuclear magnetic resonance (NMR) sequence is described herein. The method includes applying a series of refocusing pulses to a substance within an inhomogeneous static magnetic field. Each refocusing pulse in the series of refocusing pulses includes a central axis, a total pulse duration greater than t180, and at least five segments (e.g., 5, 7, 11, 20, and 21). The phase of each segment is substantially anti-symmetric about the central axis of the refocusing pulse. In a more particular embodiment, the phase of each segment is also symmetric about the central axis of the refocusing pulse and the five segments include a substantially constant amplitude.